Which situation is a good time to use a sentence fragment?

the answer is

r ≈5.641

plug in the area of 100 yards into the equation

100=

divide each side by pi

≈ 31.8309=

take the square root of each side to find r

=r

r ≈5.641

the answer is not b, and i don't think its a, so i choose either man's identity is found within the traditions of his ancestors   or language is a powerful tool, tell me if i was wrong or right by the way

what were the pronouns? did it use i, me, and my? if so, it was first person. if it had pronouns like you and your it was second person point of view. if it used he, she, and they, it was 3rd person point of view.

health care costs in the united states are on the rise.