The volume of a cylinder is given by the product of its base area (i.e. the area of a circle) and its height:

Solving for r, we have

Plugging the numbers, we have

Reflection over the y-axis = change 
Compress by a factor of k = multiply by k
So, in your case, we first change the sign of the argument. Note that this has no effect, because f(x) is symmetric with respect to the y-axis:

Then, we compress the function, multiplying it by the scaling factor:

Answer:
Step-by-step explanation:
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