Why is the cardiovascular system considered closed?

Which of these is an accurate and appropriate summary of paragraph 4? a) the speaker talks to her sister who understands politics. b) the speaker talks to her sister about all of her problems. c) the speaker wants her sister to tell her which party is best. d) the speaker is trying to find out who her sister is voting for.

Your friend goes on an all-mango diet for one month to investigate whether she can make her skin turn orange. which of the following will be most deficient in this diet? a. minerals b. dietary fiber c. amino acids d. vitamins

What are the two things that all sociologists do in their studies?