Indra completed 85% of a Multiple Choice Test in Science. She has 3
questions to complete.
(a) How many questions are there in the test?

Answers

Answer 1

Answer:

20 questions

Step-by-step explanation:

There is 15% of the test left and 3 questions

15/3 = 5

85/5 = 17

17+ 3 = 20


Related Questions

Find the zeros of the function y=x(x+2)(x-4)

Answers

Answer:

first x= -2

second x= 2

third x= 4

NO LINKS!!!! Find each measurement indicated. Round your answer to the nearest tenth. Part 2c​

Answers

9514 1404 393

Answer:

BC = 24.0AC = 26.0m∠B = 73.4°m∠B = 30.0°

Step-by-step explanation:

The law of sines tells you the ratio of sides is the same as the ratio of sines of their opposite angles.

This post has 2 kinds of problems.

1) 2 angles and the side between them are given.

2) 2 sides and the angle opposite the longest is given.

For the first type, you need to determine the missing angle (opposite the given side). That comes from the sum of angles of a triangle being 180°. Then you find the remaining sides using the ratio of sines.

For the second type, the angle opposite the shorter side is found using the ratio of sides to find the sine of that angle. Then the third side and third angle can be found using the ratio of sides to find the sine of the angle, and using the ratio of sines to find the missing side.

Straightforward, and tedious. For more than one, I like to use a spreadsheet to crunch the numbers.

_____

1) BC = 24.0

2) AC = 26.0

3) m∠B = 73.4°

4) m∠B = 30.0°

__

In the spreadsheet, the given values are in the first 3 columns. The 4th column is the first one calculated. As indicated above, the angle calculation for problems 1 and 2 uses the sum of angles relation. For problems 1 and 2, this is the angle opposite the given side. The "first side" is the side opposite the "first angle". c = b·sin(C)/sin(B), for example.

For problems 3 and 4, the first unknown angle is the one opposite the "short side", which is the shorter of the given sides. As it happens, this is the side that is asked for in the question. B = arcsin(c·sin(B)/sin(C))

_____

Additional comment

In a spreadsheet, angles are presumed to be in radians for all of the trig functions. We use the DEGREES( ) and RADIANS( ) functions to convert as appropriate.

Find the length of the missing side

Answers

Answer:

it should be 40 in.

Step-by-step explanation:

because you have to use pythagorean theorem which is A square plus B square equals C square

Hope it helps.

Which statement is true for the values of Pand Q on this number line? + Q + -2 1 -4 -3 0 1 A 응 4 B. PxQ5 C P+Q> -4 D P - Qo​

Answers

The correct answer is C hope this helps :)

Question 6
2 pts
Charlotte invested $100 per year into a business for 3 years. The total value of her
investment after 3 years is represented by the algebraic expression below, where x is the
growth in value each year.
100 (x3 + x2 + x)
What is the total value of her investment when x = 2?
O $6400
O $1200
O $600
O $1400

Answers

1200, (2)3+(2)2+2 = 6+4+2 = 12 12(100)= 1200

What coordinates will remain the same? What coordinates will change to the opposite between the pre-- and post-image?

Answers

Answer:

Y values will stay the same

Step-by-step explanation:

Reflecting over the Y axis will alter the distance left and right but not up and down. so only Y remains unchanged

An article reports the following data on yield (y), mean temperature over the period between date of coming into hops and date of picking (x1), and mean percentage of sunshine during the same period (x2) for the Fuggle variety of hop:

x1: 16.7 17.4 18.4 16.8 18.9 17.1 17.3 18.2 21.3 21.2 20.7 18.5
x2: 30 42 47 47 43 41 48 44 43 50 56 60
y: 210 110 103 103 91 76 73 70 68 53 45 31

Use the following R Code to complete the regression analysis:
x1 = c(16.7, 17.4, 18.4, 16.8, 18.9, 17.1, 17.3, 18.2, 21.3, 21.2, 20 7, 18.5)
x2 = c(30, 42, 47, 47, 43, 41, 48, 44, 43, 50, 56, 60)
y = c(210, 110, 103, 103, 91, 76, 73, 70, 68, 53, 45, 31)

Required:
According to the output, what is the least squares regression equation ŷ = bo + b1x1 + b2x2:

Answers

Answer:

[tex]y = 415.113 -6.593 x_1 -4.504 x_2[/tex]

Step-by-step explanation:

Given

[tex]x_1: 16.7\ 17.4\ 18.4\ 16.8\ 18.9\ 17.1\ 17.3\ 18.2\ 21.3\ 21.2\ 20.7\ 18.5[/tex]

[tex]x_2: 30\ 42\ 47\ 47\ 43\ 41\ 48\ 44\ 43\ 50\ 56\ 60[/tex]

[tex]y: 210\ 110\ 103\ 103\ 91\ 76\ 73\ 70\ 68\ 53\ 45\ 31[/tex]

Required

Use R code to determine the regression equation

[tex]y = b_o + b_1x_1 + b_2x_2[/tex]

First, write the following code in a R program

[tex]x1 <- c(16.7,17.4,18.4,16.8,18.9,17.1,17.3,18.2,21.3,21.2,20.7,18.5)[/tex]

[tex]x2 <- c(30,42,47,47,43,41,48,44,43,50,56,60)[/tex]

[tex]y <- c(210,110,103,103,91,76,73,70,68,53,45,31)[/tex]

[tex]mod <- lm(y[/tex]~[tex]x1+x2)\\[/tex]

[tex]summary(mod)[/tex]

Next, run the program

See attachment for program and output

From the output, go to coefficients:

Check Estimate Std. column, you have the following:

[tex](Intercept) = 415.113[/tex]

[tex]x_1 = -6.593[/tex]

[tex]x_2 = -4.504[/tex]

[tex]y = b_o + b_1x_1 + b_2x_2[/tex] implies that:

[tex]b_o \to[/tex] Intercept

[tex]b_1 \to x_1[/tex]

[tex]b_2 \to x_2[/tex]

Hence, the least square regression equation is:

[tex]y = 415.113 -6.593 x_1 -4.504 x_2[/tex]

Why did the farmer open a bakery?

Answers

Answer:

yes

Step-by-step explanation:

yes

Answer:

Step-by-step explanation:

Farmers usually open bakery's to sell their produce or ship them to grocery stores like Walmart, Cosco, etc. I hope this answered your question since I don't quite understand...

Q8. How many solutions does the system of equations have?

Answers

Answer:

it would be the first answer

Step-by-step explanation:

a solution is where the lines meet, and the coorinate is (1,4)

the answer would b A !

what is the volume of a bow with a width of 3/2 inches a length of 5/2 inches and a height of 4 inches

Answers

Answer:

v=LxWxH

v= 3/2x5/3x4

v=15/6x4

v=10in³

help ugent!
12 + 2 + 2 + 2 + 2 + 2 ^ 2=

Answers

[tex]24.[/tex]

Step-by-step explanation:

[tex]12 + 2 = 14.[/tex]

[tex]14 + 2 = 16.[/tex]

[tex]16 + 2 = 18.[/tex]

[tex]18 + 2 = 20.[/tex]

[tex]20 + {2}^{2} = 24.[/tex]

Note:- 2² = 2×2 = 4. So, 2² = 4.

Answer:

24

make sure you calculate the answer next time!

Jeremy bought 5/10 kg of mangoes, 3/4 kg of bananas and 1/2 kg of papayas. How many kilograms of fruits did he buy in all?

Answers

Answer:

add 5/10+3/4+1/2 you add number i will give you hint

Write the algebraic expression: 4p times the sum of 7 and 5p​

Answers

Answer:

4p(7 + 5p)

Step-by-step explanation:

4p times the sum of 7 and 5p​

4p(7 + 5p)

I’ll give brainliest if correct!



Question 16 of 43
For the data set 9, 13, 14, 15, 15, 18, the mean is 14. What is the mean
absolute deviation?
O A. The mean absolute deviation is 14.
O B. The mean absolute deviation is 12.
O C. The mean absolute deviation is 2.
D. The mean absolute deviation is 6.

Answers

Answer:

C. The mean absolute deviation is 2.

Step-by-step explanation:

In order to find the mean absolute deviation, follow the following steps:

Find the absolute distance of each data from the mean. Add the distances so obtained Divide the sum by no of given data to get the mean absolute deviation.

Let's work it out.

STEP: 1

|9 - 14| = 5

|13 - 14| = 1

|14 - 14| = 0

|15 - 14| = 1

|15 - 14| = 1

|18 - 14| = 4

STEP: 2

5 + 1 + 0 + 1 + 1 + 4 = 12

STEP: 3

Mean Absolute deviation [tex] =\frac{12}{6}= 2[/tex]

Please help me fast. I’m confused.

Find the value of x.
168
x = [? ]°

Answers

Answer: 84

Step-by-step explanation:

The horizontal line is the line tangential to a circle. The measure of the missing angle "x" is 84 degrees

Circle geometry.

From the figure given, the horizontal line is the line tangential to a circle.

Given the following parameter

measure of minor arc = 168 degrees

Required

angle at the vertex "x"

Using the theore " angle the vertex is half of the measure of its intercepted arc. Mathematically;

x =1/2 minor arc

x= 1/2 (168)

x = 84 degrees

Hence the measure of the missing angle "x" is 84 degrees

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Can you please help me

Answers

Answer:

is there amultipe choice answer if so list them down

Step-by-step explanation:

Russell surveyed 16 students at his school and found that 4 of them planned to take orchestra as their next elective. If Russell surveys 12 more students, how many of them are probably planning on taking orchestra as an elective, based on past data?

Answers

Answer:3

Step-by-step explanation:

The probability that the number of students who take orchestra as an elective is 1/4 and the number of students who joined extra is 4

What is Probability?

The probability that an event will occur is measured by the ratio of favorable examples to the total number of situations possible

Probability = number of desirable outcomes / total number of possible outcomes

The value of probability lies between 0 and 1

Given data ,

Let the probability that the number of students who take orchestra as an elective be represented as P

Now , the equation will be

The total number of students = 16 students

The number of students who opted for orchestra as elective = 4 students

So , the probability that the number of students who take orchestra as an elective P = number of students who opted for orchestra as elective / total number of students

Substituting the values in the equation , we get

The probability that the number of students who take orchestra as an elective P = 4/16

The probability that the number of students who take orchestra as an elective P = 1/4 = 25 %

Now , when the number of students = 16 + 12 = 28 students

The probability that the number of students who take orchestra as an elective P₁ = ( x + 4 ) / 28

Substituting the values in the equation , we get

1/4 = ( x + 4 ) / 28

Multiply by 28 on both sides of the equation , we get

x + 4 = 7

Subtracting 4 on both sides of the equation , we get

x = 3 students

So , the number of students who will take orchestra from the group of 12 students is 3 students

Hence , the probability is 1/4

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lemme explain, im a middle schooler and my school just jumped into this with no explanation.​

Answers

Answer:

the first question is c

Step-by-step explanation:

2 x pi x the radius

2 x 3.14 x 8


Which graph represents the equation y=-
--*x+3?
B)
t

Answers

Answer:

The correct answer would be the 3rd graph!

Hope this helps!

Please help me answer this ASAP!

Answers

Answer: z=25 x=114

Step-by-step explanation:

When oil is spilled in water, it creates a thin film of water approximately 1 micron thick. A barrel of oil is approximately 42 gallons of oil. If we spill a barrel of oil on the water, what is the area covered by the oil slick

Draw a sketch showing the relevant dimensions.
State your answer in square meters.
State your answer in square kilometers.

Answers

9514 1404 393

Answer:

158,987 m²0.158986 km²

Step-by-step explanation:

42 gallons is about 0.158987 cubic meters. 1 micron is 1 micro-meter, or 10^-6 meters. The volume is the product of the area and thickness. For some area A, we have ...

  0.158987 m³ = (10^-6 m)A

  A = (10^6)(0.158987 m² = 158,987 m²

The area in square meters is 158,987.

__

A square km is (1000 m)² = 10^6 m². So, the area in square kilometers is about ...

  (158,987 m²)/(10^6 m²/km²) = 0.158987 km²

The area in square km is about 0.1590.

The National Collegiate Athletic Association (NCAA) requires colleges to report the graduation rates of their athletes. At one large university, 91% of all students who started their studies in 2000-2010 graduated within 6 years. A sports reporter contacted 152 athletes randomly sampled from that same university and time period and found that 132 of them had graduated within 6 years.
(a) (5 points) Perform the appropriate hypothesis test to determine whether this is significant evidence that the percentage of athletes who graduate is less than for the student population at large, using the significance level a = 0.05. Remember for state the null and alternative hypotheses, the decision rule, and your conclusion.
(b) (3 points) Calculate the P-value for this test. Explain how this P-value can be use to test the hypotheses in part (a).

Answers

Answer:

a)

The null hypothesis is [tex]H_0: p = 0.91[/tex].

The alternate hypothesis is [tex]H_1: p < 0.91[/tex].

The decision rule is: accept the null hypothesis for [tex]z > -1.645[/tex], reject the null hypothesis for [tex]z < -1.645[/tex].

Since [tex]z = -1.79 < -1.645[/tex], we reject the null hypothesis and accept the alternate hypothesis that that percentage of athletes who graduate is less than for the student population at large.

b)

The p-value for this test is 0.0367. Since this p-value is less than the significance level of [tex]\alpha = 0.05[/tex], we reject the null hypothesis and accept the alternate hypothesis that that percentage of athletes who graduate is less than for the student population at large.

Step-by-step explanation:

Question a:

Perform the appropriate hypothesis test to determine whether this is significant evidence that the percentage of athletes who graduate is less than for the student population at large:

At the null hypothesis, we test if the proportion is the same as the student population, of 91%. Thus:

[tex]H_0: p = 0.91[/tex]

At the alternate hypothesis, we test that the proportion for athletes is less than 91%, that is:

[tex]H_1: p < 0.91[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

Test if the proportion is less at the 0.05 level:

The critical value is z with a p-value of 0.05, that is, z = -1.645. Thus, the decision rule is: accept the null hypothesis for [tex]z > -1.645[/tex], reject the null hypothesis for [tex]z < -1.645[/tex].

0.91 is tested at the null hypothesis:

This means that [tex]\mu = 0.91, \sigma = \sqrt{0.91*0.09}[/tex]

A sports reporter contacted 152 athletes randomly sampled from that same university and time period and found that 132 of them had graduated within 6 years.

This means that [tex]n = 152, X = \frac{132}{152} = 0.8684[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{0.8684 - 0.91}{\frac{\sqrt{0.91*0.09}}{\sqrt{152}}}[/tex]

[tex]z = -1.79[/tex]

Since [tex]z = -1.79 < -1.645[/tex], we reject the null hypothesis and accept the alternate hypothesis that that percentage of athletes who graduate is less than for the student population at large.

(b) (3 points) Calculate the P-value for this test. Explain how this P-value can be use to test the hypotheses in part (a).

The p-value of the test is the probability of finding a sample proportion of 0.8684 or below. This is the p-value of z = -1.79.

Looking a the z-table, z = -1.79 has a p-value of 0.0367.

The p-value for this test is 0.0367. Since this p-value is less than the significance level of [tex]\alpha = 0.05[/tex], we reject the null hypothesis and accept the alternate hypothesis that that percentage of athletes who graduate is less than for the student population at large.

The CEO of a large manufacturing company is curious if there is a difference in productivity level of her warehouse employees based on the region of the country the warehouse is located. She randomly selects 35 employees who work in warehouses on the East Coast (Group 1) and 35 employees who work in warehouses in the Midwest (Group 2) and records the number of parts shipped out from each for a week.
She finds that East Coast group ships an average of 1276 parts and knows the population standard deviation to be 347.
The Midwest group ships an average of 1439 parts and knows the population standard deviation to be 298.
Using a 0.01 level of significance, test if there is a difference in productivity level. What is the test statistic?
(Round to 4 decimal places)
z =
please use excel to solve

Answers

Answer:

The test statistic is z = -2.11.

Step-by-step explanation:

Before finding the test statistic, we need to understand the central limit theorem and subtraction of normal variables.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

Group 1: Sample of 35, mean of 1276, standard deviation of 347.

This means that:

[tex]\mu_1 = 1276, s_1 = \frac{347}{\sqrt{35}} = 58.6537[/tex]

Group 2: Sample of 35, mean of 1439, standard deviation of 298.

This means that:

[tex]\mu_2 = 1439, s_2 = \frac{298}{\sqrt{35}} = 50.3712[/tex]

Test if there is a difference in productivity level.

At the null hypothesis, we test that there is no difference, that is, the subtraction is 0. So

[tex]H_0: \mu_1 - \mu_2 = 0[/tex]

At the alternate hypothesis, we test that there is difference, that is, the subtraction is different of 0. So

[tex]H_1: \mu_1 - \mu_2 \neq 0[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{s}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis and s is the standard error.

0 is tested at the null hypothesis:

This means that [tex]\mu = 0[/tex]

From the two samples:

[tex]X = \mu_1 - \mu_2 = 1276 - 1439 = -163[/tex]

[tex]s = \sqrt{s_1^2+s_2^2} = \sqrt{58.6537^2+50.3712^2} = 77.3144[/tex]

Test statistic:

[tex]z = \frac{X - \mu}{s}[/tex]

[tex]z = \frac{-163 - 0}{77.3144}[/tex]

[tex]z = -2.11[/tex]

The test statistic is z = -2.11.

A sample of 300 subscribers to a particular magazine is selected from a population frame of 9,000 subscribers. If, upon examining the data, it is determined that no subscriber had been selected in the sample more than once:________.
A. the sample could not have been random
B. the sample may have been selected without replacement or with replacement
C. the sample had to have been selected without replacement
D. the sample had to have been selected with replacement

Answers

Answer:

C

Step-by-step explanation:

It is determined that no subscriber had been selected in the sample more than once the sample had to have been selected without replacement.

What is the sample?

A sample is a subset of data drawn from a larger population by a researcher using a predetermined selection process. These components are referred to as sample points, sampling units, or observations.

If it is determined that no subscriber had been selected in the sample more than once, this means that each subscriber was only included once in the sample. This can only occur if the sample was selected without replacement, meaning that each subscriber was selected once and only once from the population frame.

Therefore, the correct answer is C. the sample had to have been selected without replacement.

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Hi help me out thank youu love

Answers

Answer:

636

Step-by-step explanation:

SA=2LW+2LH+2WH

SA= 2(12)(10)+2(12)(9)+2(10)(9)= 636

Answer:

The answer is 636

Step-by-step explanation:

Brainliest maybe?

:)

id also appreciate help on this one ^^

Answers

Answer:

The area of the given figure is 87.55 cm square.

A box, containing 25 bolts and 25 washers, has a mass of 475 g. Another box, containing 17 bolts and 34 washers, has a mass of 442 g. Determine the mass of one bolt and the mass of one washer

Answers

Answer:

bolts=12g and washers=7 g

Step-by-step explanation:

honestly, i tried to solve this by hand and made an error somewhere, but i set up two equations, then tried to use elimintation to solve for one variable. but in the end i went to my trusty calculator and created a matrix, then used the rref math to solve. sorry i couldnt be of more help

to bake a cake, the recipe calls for 6 eggs. Arline wants to bake 24 cakes for her schools bake sale. how many eggs will she need in all for the 24 cakes?

Answers

The answer is 144.

Answer:

144 eggs

Step-by-step explanation:

1 cake = 6 eggs

24 * 6 = 144 eggs in total.

A longer way to do it is by adding 6, 24 times.

6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6 = 144

But by multiplying, it makes it easier to find the answer.

Help me plz I did the first problem

Answers

Answer:

b. 30 > 2d

   15 > d

c. 15/f < 5

   15 < 5f

   5 < f

d. 42 [tex]\leq[/tex] 50 - m

   42 + m [tex]\leq[/tex] 50

   m [tex]\leq[/tex] 8

evan is sending a package of some of his produce to his friend in California. The package measures 12 by 9 by 6 inches. He wraps it in brown paper, addresses it, and takes it to the post office to mail. How much brown paper will he need to wrap the box ____in2

Answers

Answer:

[tex]468in^{2}[/tex]

Step-by-step explanation:

L=12

W=9

H=6

2lw+2lh+2wh=468

Many think ts, "oh LWH" well actually lwh is volume

The brown paper required to wrap the package is 468 square inches.

What is a cuboid?

A cuboid is a three-dimensional shape in which all sides are rectangles. A cuboid has 6 faces, 8 vertices, and 12 edges. All the angles formed at the vertices of a cuboid are right angles. The opposite edges are parallel to each other.

For the given situation,

The diagram shows the package that is cuboid in shape.

The dimensions of cuboid are

The length of the cuboid = 12 in

The wide of the cuboid = 9 in

The height of the cuboid = 6 in

The package is wrapped using the brown paper. The brown paper needed can be calculated by using the surface area formula,

[tex]A=2(lw+hl+hw)[/tex]

⇒ [tex]A=2[(12)(9)+(6)(12)+(6)(9)][/tex]

⇒ [tex]A=2[108+72+54][/tex]

⇒ [tex]A=2[234][/tex]

⇒ [tex]A=468[/tex]

Hence we can conclude that the brown paper required to wrap the package is 468 square inches.

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Other Questions
Please help me fast. Im confused.Find the value of x.168x = [? ] What is the surface area of the cylinder with height 2 yd and radius 3 yd? Round your answer to the nearest thousandth. Ill give brainliest if correct!Question 16 of 43For the data set 9, 13, 14, 15, 15, 18, the mean is 14. What is the meanabsolute deviation?O A. The mean absolute deviation is 14.O B. The mean absolute deviation is 12.O C. The mean absolute deviation is 2.D. The mean absolute deviation is 6. How could the aquifer around the Los Angeles are in California be susceptible to an impact by a Tragedy of the Commons? (-2-3) (-2+3) when simplified is why does secondary consumers cannot digest the bones of their prey 0.2x + 0.3 = 0.1x + 0.5 For each of the salts below, match the salts that can be compared directly, using Ksp values, to estimate solubilities. a. Mg(OH)2b. CaSO3c. BaCrO4d. CaS1. copper (II) sulfide2. zinc hydroxide PLEASE HELP ASAP, WILL MARK BRAINLIEST!!!! Do noble gases lose or gain electrons to get a full valence shell? Please help me answer this ASAP! How to paraphrase this sentence: in the past many people had skills such as making their own clothes and doing repairs to things in the house. In many countries, nowadays, skills like these are disappearing. Find the simple interest paid.9. Principal: $350Annual rate: 4%Time: 3 yearsInterest When elements chemically combine with each other, what do they Form? A. electrons, B. compounds, C. atoms Hi help me out thank youu love Select the correct answer from the choices provided in the underlined sectionsA plant grown in low light will have (lighter / darker) flower color while a plant grown in bright light will have a (light / darker) flower color. The nature of warfare during World War I on the Westem and Eastern fronts can best be described asO lighting quick strikes known as "blitzkrieg"O a series of swift and decisive battlesnavy battles fought in the Pacific OceanO a war of attrition or stalemate fought primarily in trenches Why did the farmer open a bakery? 25 Which situation contributed to Adolf Hitler's rise to power in Germany after World War 1?A. Support of Hitler's radical socialist policyB. Strong feelings of resentment, anger and nationalism built up by economic and political crises.C. Refusal by the League of Nations to recognize the country of GermanyD. Violence and terrorism promoted by the United States, what is Internet?Write its importance in the today world.