Answer:
0.72secs
Step-by-step explanation:
Given the height of the ball in air modeled by the equation:
h=−16t²+23t+4
Required
Total time it spent in the air
To get this we need to calculate its time at the maximum height
At the maximum height,
v = dh/dt = 0
-32t + 23 = 0
-32t = -23
t = 23/32
t = 0.72secs
<em>Hence the total time it spend in the air will be 0.72secs</em>
The number is 69.3 because percent means 0.01, so 10 x 0.01 = 1.1
so 1.1 x 63 = 69.3. you can also do 63 x 10% = 69.3.