Answer:
B
Step-by-step explanation:
Use the formula for radius and circle circumference.

Since we know the diameter, if we divide that by 2, we can get the radius.

Now we can plug that value into the circumference formula to get the circumference.

*Since we're rounding to the nearest inch.
f(x)−4 involves translating the graph of f(x) DOWN by 4 units.
4f(x) involves vertical stretching of the graph by a factor of 4.