Will somebody please help answer this question?

Aman steps out of a plane at a height of 4,000m above the ground falls 2,000m very quickly and then opens his parachute and slowly falls the remaining 2000m to the ground what height above the ground would be the best choice for a reference point

Simplify the expression and find the missing terms. the simplest form of has in the numerator and in the denominator.

This is different from the first one can someone me