If a rock had 80 radioactive atoms in it when it was formed and it now has 40 radioactive elements in it, how old is the rock?

What is the capital city of Nepal ? About 3,000 years ago, the _____ civilization flourished in what is now Mexico's Yucatn Peninsula, Guatemala, and Belize. A. Anasazi B. Olmec C. Aztec D. Maya solve by substitution 3x +y=13 and 5x-2y=7 Solve: 3(x- 2)= 18. X= Whom do aquatic veterinarians treat?OA.marine animalsmammalsO c.birdsOD.catsO E. dogs if the cost of 1 packet biscuit is Rs.17.50,what is the cost of 8 packets of biscuits? Find the solution of the system of equations.7x + 14y = 21- 2 + 7y = 6 How many sides does a regular polygon have if each of its interior angles is 140 degrees?- Step by step explanation PLEASE HELP ME ASAP!! ILL GIVE YOU POINTS AND BRAINLIEST IF YOU ANSWER ALL 3 TRUE OR FALSE QUESTIONS CORRECTLY. A) Slope=8 True or False? B) Unit Rate= $8/hour True or False? C) The equation of this relationship is y= 1/8x True or False? If you go to your local library to vote, this public building would be considered your. A sum of money amounts to 9800 after 5 years and 12005 after 8 years at the same rate of simple interest. What will be the rate of interest?[Irrelevant answers will be reported] Gill had less money than Roddy hadAfter Roddy spent 40% of his money,he had $14 less than Gill. How muchmoney did Gill initially have? What did Radical Republicans want from the Southern states before theycould rejoin the Union? is -12(-8) negative vaule Grade 7 collection 6 test During Reconstruction in the South, most white Southerners welcomed legislation supporting freed African Americans. worked closely with African Americans to rebuild the South. resented the destruction of the Southern economy. joined the Ku Klux Klan, especially those who lived in cities. Plzz Help easy quesion for 20 points Why does someone get burned if they touch an old filament bulb that has been on for a few hours? Plzz Help The regular price of a jacket is $62.00. If the discount rate is 15%, how much was the discount? 10x- (- 4 + 7xanswer if you can :) Draw something grotesque that oozes or is melting.WIll give brainliest if you send me a picture!!