Answer:

Step-by-step explanation:
We are given with two equations
first equation is 
second equation is

we find the result of subtracting two equation
subtract the second equation from the first, so
first equation - second equation, multiply second equation by -1 and then add it with first equation


Now add both equations, we get

174.97$ is the answer.
How I did it:
419.92 / 2.4 = 174.966 which rounds to 174.97$
The answer is 6 since the scale factor is 2 and 3x2 is 6
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Find Radius :
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Find volume of the cylinder :
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Find volume of the gap :
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A positive number
This is because you must add to get from a negative number in order to get to a positive number.