30 POINTS! PLEASE HELP.

Which of the following are two examples of ways that objects can have potential energy?

A. A boulder that is falling after being pushed off a cliff.

B. A Iron nail as it move towards a magnet.

C. A pebble in a slingshot before it has been shot.

D. A pebble traveling as it is shot with a slingshot.

Read the sentences below in 1962, i tried to enroll as the first black student at the university of mississippi. the governor of mississippi blocked my entrance which best describes the verbs used in the sentences? o they are past tense verbs, which are often used in narrative essays o they are past tense verbs, which are not often used in narrative essays. o they are future tense verbs, which are often used in narrative essays o they are future tense verbs, which are not often used in narrative essays.