Answer:
12
Step-by-step explanation:
The toy rocket hits the ground when h(t) = 0.
So, h(t) = 0 = -9t^2 + 81.
Solving the equation,
-9t^2 = -81
Dividing by -9
t^2 = 9
Taking the square root.
t = 3
The answer is 3 seconds.
Answer:
78.5 cm
Step-by-step explanation:
C=2 X pi X r
r= radius
then divide by 2 for a half circle
Answer:
175 * 2 * 
350
radians
Step-by-step explanation: