A smoke jumper jumps from a plane that is 1800 ft above the ground. The function h=-16^2 + 1800 gives the jumper's height h in feet during the free fall at t seconds.

Question

a. How long is the jumper in free fall if the parachute opens at 1000​ ft?
b. How long is the jumper in free fall if the parachute opens at 950 ft?

What is a reasonable range for the function​ h?
-1800<h<1800
0<h<1800
-10<h<10
0<h<10
All real numbers

What is a reasonable domain for the function​ h?
0<t<10
0<t<1800
-1800<t<1800
-10<t<10
All real numbers

Answer 1

so, in the 6 hours since you last posted this, have you made any headway in the solution?
(a) solve -16t^2 + 1800 = 1000
(b) solve -16t^2 + 1800 = 950

surely, knowing what you do about parabolas, you can determine the range, since the vertex is at (0,1800) and the parachute does not burrow into the ground.

and the domain is surely only during the actual fall time 0 < t < √(1800/16)

don't get spooked by the equations and stuff -- think about the actual meaning and events happening.