I need help answer this question..

What is the volume of a rectangular prism that is 120 centimeters by 2 meters by 1.5 meters in cubic meters?

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?

What function has a range {yly< 5}? question on picture above^