3. how much a machine changes its input force is its __
input output
mechanical advantage
none of the above
plz

Mechanical advantage is the answer.

Option B.

A machine is defined as the instrument which is used to perform some task easily, and with ease. A machine has the capability to give an output force in exchange of an input force. Now the ratio of the output force to input force is called as the mechanical advantage.

Mechanical advantage = Output force / input force.

For example, in case of a lever, there are three types - first class lever, second class lever, and third class lever. Mechanical advantage for a second class lever is always more than one, as we get more output force than input force. Similarly, the mechanical advantage for a third class lever is always less than 1, and mechanical advantage of first class lever can be both more or less or equal to one.