Well, Brainly really doesn't like questions that are lifted straight out of exams, tests, or quizzes, so there's only so much I can say.
... You've GOT the formula for the height h at any time t .
... It TELLS you to find t when h=0.
... So write the equation
-16 t^2 + 32 t = 0
and then solve the equation to find t .
You'll find two solutions for t . One of them is. t=0 . This reveals the mind-blowing fact that the instant before the rocket was launched, at t=0, the rocket was on the ground. The other solution for t will tell you how many seconds after launch the rocket is back on the ground.
