Answer: The volume of shell is 12.8π mm².
Step-by-step explanation:
Since we have given that
Radius to the inside of the shell = 4 milimeters
Radius to the outside of the shell = 4.2 milimeters
Since r changes from 4 mm to 4.2 mm
so,
As we know that
Volume of shell is given by
So, the volume of shell is 12.8π mm².
The question is incomplete. Here is the complete question.
Raoul measured the ehight of 12 different plants in his garden in April. He measured them again in June.
April Heights (in inches) 12 15 23 11 42 45 44 39 12 19 20 12
June Heights (in inches) 45 45 40 43 11 14 12 13 41 40 45 41
What is the difference between the mean height in April and the mean height in June?
Answer: The difference between means is 8.0
Step-by-step explanation: <u>Mean</u> is the average of a set of numbers.
It is calculated as:
where
x is the numbers in the set
n is how many numbers are there in the set
For heights in April, the mean is:
μ₁ = 24.5
For heights in June, the mean os:
μ₂ = 32.5
The difference between means:
μ₂ - μ₁ = 32.5 - 24.5 = 8.0
The difference between the mean height in April and in June is 8.0 inches.