Asphere has a diameter of 14 units what is the volume of the sphere in cubic units you must show the formula and your work use 3.14 for pi and round your answer to the nearest : )

Suppose that sahil knows that 45 people with ages of 18 to 29 voted. without using a calculator, he quickly says then 135 people with ages of 30to 49 voted. is he correct? how might sohil have come up with his answer so quickly?