There are two right circular cylinders. The radius of the first cylinder is 3 centimeters, and its height is 5 centimeters. The radius of the second cylinder is 15 centimeters, but its height is also 5 centimeters. What is the ratio of the volume of the second cylinder to the volume of the first cylinder? A. 9:1 B. 16:1 C. 36:1 D. 25:1 please help ASAP

Answer asap ill give ! ’ a sample of radioactive material decays over time. the number of grams, y , of the material remaining x days after the sample is discovered is given by the equation y = 10(0.5)^x. what does the number 10 represents in the equation? a. the half-life of the radioactive material, in days b. the amount of the sample, in grams, that decays each day c. the time, in days, it will take for the samples to decay completely d. the size of the sample, in grams, at the time the material was discovered