When thrown upward at a velocity of 16 feet per second, the height f of an object in feet at the end of t seconds is given by the formula f =-16t+16t?
After approximately how many seconds will an object reach a height of 32 feet?
5 seconds
2 seconds
3 seconds
None of the choices are correct.

b) 2 seconds

t=2 seconds will an object reach a height of 32 feet

Step-by-step explanation:

Explanation:-

Given  height  f =-16t+16t² ...(i)

Differentiating equation (i) with respective to 't'

Equating Zero

- 32 t + 16(2t) =0

 - 16 t = -32

        t = 2 seconds

Given height   f =-16t+16t²

                      f = - 16 (2) +16(4) = -32 +64= 32feet

Conclusion:-

t=2 seconds will an object reach a height of 32 feet