Question 1175980
a) max height reached at -b/2a


h(t) = -16t^2 + 1600t


-b/2a = 1600/32 = {{{50}}} seconds


b) We want the solutions to -16t^2 + 1600t = 0.


t = 0 or t = 100. Time can't be zero or negative, so the bullet reaches the ground after 100 seconds.