If your bike wheel has a diameter of 2.5 feet, how many times does the wheel make a full rotation?

How to solve it and what thw answer is

Which of the following would represent the sum of 3 consecutive integers if x is the first integer?

Initially 100 milligrams of a radioactive substance was present. after 6 hours the mass had decreased by 4%. if the rate of decay is proportional to the amount of the substance present at time t, find the amount remaining after 24 hours. (round your answer to one decimal place.)