Volume of a Cylinder = pi * r^2 * h
V / (pi*r^2) = h
12157 / (pi * 9^2) = h = 47.774
Answer:
The number of possible three-digit phone prefixes that are used to represent a particular geographic area is 640.
Step-by-step explanation:
The phone prefixes used to represent a particular geographic area are a 3 digit code consisting of numbers from 0 to 9.
The prefix code are of the form: <u>x</u> <u>x</u> <u>x</u>
Condition: The first or the second place cannot take values 0 or 1.
Then the first place can be occupied by the remaining 8 digits.
Similarly the second place can also be occupied by the remaining 8 digits.
And the third place can be occupied by any of the 10 digits.
So the number of ways to construct a phone prefix for any area is:

Thus, the number of phone prefixes possible for any area is 640.
Answer:
Wow everyone is being so noice today is today some kind of special occassion?
It's too blurry to read. If you tell me what it says, I'll try to give you an answer.