Answer:
30 s
Step-by-step explanation:
When the ball hits the ground h=0. To find the time t when this happens we must solve the equation h=0.
●h= 0
● -12t^2+360t =0
● t(-12t +360) = 0
● t = 0 or -12t +360 =0
● t=0 or -12t = -360
● t=0 or 12t =360
● t=0 or t=360/12
● t=0 or t= 30
The equation has two solutions.
The ball was fired with an initial speed of 800 feet per second so it cannot hit the ground at t=0.
So the ball hits the ground after 30 s.
Answer: n = 14
Step-by-step explanation: margin of error = critical value × σ/√n
Where σ = population standard deviation = 1
n = sample size = ?
We are to construct a 99% confidence interval, hence the level of significance is 1%.
The critical value for 2 tailed test at 1% level of significance is gotten from a standard normal distribution table which is 2.58
Margin of error = 0.7
0.7 = 2.58×1/√n
0.7 = 2.58/√n
By cross multipying
0.7×√n = 2.58
By squaring both sides
0.7^2 × n = 2.58^2
0.49 × n = 6.6564
n = 6.6564/0.49
n = 14
Answer:
Estimate: 700 Answer: 712
Answer:
x > -7 is true because there are more tennis balls than -7
Step-by-step explanation:
Answer:
A table?
Step-by-step explanation:
fingers crossed this is right
