Answer: 2/9
Step-by-step explanation:
Simplify the expression.
Answer:
Between 12.614 years and 16.386 years
Step-by-step explanation:
Given that:
Mean age (μ) = 14.5 years, standard deviation (σ) = 4.6 years, number o sample (n) and the confidence interval (c) = 90% = 0,9
α = 1 -c = 1 -0.9 = 0.1

The z score of
is the same as the z score of 0.45 (0.5 - 0.05). This can be gotten from the probability distribution table. Therefore:

The margin of error (e) =
= 
The interval = μ ± e = 14.5 ± 1.886 = (12.614 ,16.386)
The formula for the volume of a quarter-sphere is simply one-fourth of the volume of the sphere. So the volume of a quarter-sphere:
V = (1/4) (4/3) (π r³)
or
V = (1/3) (π r³)
Since we are given with the radius of 70 feet, the volume is
V = (1/3) (π) (70³)
V = 359,189 cubic feet