Answer:
a
Step-by-step explanation:
20 cm * 1 inch / 2.54 cm =
<span>
<span>
<span>
7.874015748
</span>
</span>
</span>
inches
So the approximate result is 20 cm = 7.9 inches
Answer: (2.54,6.86)
Step-by-step explanation:
Given : A random sample of 10 parking meters in a beach community showed the following incomes for a day.
We assume the incomes are normally distributed.
Mean income : 
Standard deviation : 


The confidence interval for the population mean (for sample size <30) is given by :-

Given significance level : 
Critical value : 
We assume that the population is normally distributed.
Now, the 95% confidence interval for the true mean will be :-

Hence, 95% confidence interval for the true mean= (2.54,6.86)
Answer:
1414 kL
Step-by-step explanation:
The volume of the donut-shaped moat is the product of its surface area and depth. The area is the product of its centerline length and its width.
<h3>Moat area</h3>
The diameter of the centerline of the moat is (50 m -5 m) = 45 m. The length of that centerline is ...
C = πd = π(45 m) = 45π m
The area is this length times the width of the moat:
moat area = (45π m)(5 m) = 225π m²
<h3>Moat volume</h3>
The volume is the product of the area and the depth of the moat:
V = Ah = (225π m²)(2 m) = 450π m³ ≈ 1413.72 m³
1 cubic meter is 1000 liters, 1 kiloliter.
The volume of the moat is about 1414 kL.