if a stone at the end of a string is whirled in a circle, the inward pull on the stone

Question

A) is known as the centrifugal force
B) is inversely proportional to the speed of the object
C) is inversely proportional to the square of the speed
D) is proportional to the speed
E) is proportional to the square of the speed

plzz help me soon

Answer 1

A) is known as the centrifugal force
E) is proportional to the square of the speed

Answer 2

is propotional to the square of speed
as we know that
fc=mv^2/r

Answer 3

proportional to the speed

Answer 4

A) is known as the centrifugal force