Answer:
2.74 seconds
Step-by-step explanation:
The apple will hit the ground when its height above the ground is zero:
0 = -16t^2 +120
t^2 = 120/16 . . . . . . divide by 16 and add t^2, then simplify and take the square root:
t = √7.5 ≈ 2.73861 ≈ 2.74 . . . . seconds
