Hello. This question is incomplete. The full question is:
"Which statement best describes why a machine is useful? A-A machine does a greater amount of work than the amount of work that is done on it. B-A machine does a smaller amount of work than the amount of work that is done on it. C-A machine can decrease both the input force and the input distance needed to do a given amount of work. D-A machine can decrease either the input force or the input distance needed to do a given amount of work."
Answer:
D-A machine can decrease either the input force or the input distance needed to do a given amount of work.
Explanation:
A machine is a device that uses energy and work to achieve a predetermined goal. In Physics, any device that changes the direction or intensity of a force with the use of work. In summary, we can say that what best describes why a machine can decrease the input force or the input distance needed to perform a certain amount of work, for this reason, the machine is useful.
