Hay Guys! Can anybody help me in Math lesson about the "Pyramid" in the height? Which height should I choose for the formula the inner one or the outer one?

Thank u. ​

Two planes leave an airport at the same time, one flying east, the other flying west. the eastbound plane travels 20 mph slower. they are 1600 mi apart after 2 hr. find the speed of each plane.

What is the product? a-3/15a × 5/a-3

What is the arc length of the subtending arc for an angle of 72 degrees on a circle of radius 4? o a. 8a oc. 16 t d. 8