Apine cone drops from a tree branch that is 36 feet above the ground. the function h = –16t2 + 36 is used. if the height h of the pine cone is in feet after t seconds, at about what time does the pine cone hit the ground? could 2 seconds be a reasonable answer to this model?

We have that
h = –16t² + 36

using a graph tool
see the attached figure
the x-intercept is when the pine cone hit the ground
h=0 for t=1.5 sec

therefore

the answer part a) is
1.5 seconds

Part b)Could 2 seconds be a reasonable answer to this model?
h = –16t² + 36
for t=2 sec
h=-16*(2)²+36-------> h=-64+36------> h=-25 ft

the answer Part b) is
2 seconds is not a reasonable answer to this model, because the height h of the pine cone cannot be negative
the domain of the model is for the values of t included in the interval [0,1.5]