So sánh hệ tuần hoàn kín đơn và hệ tuần hoàn kín kép ,hệ tuần hoàn nào có ưu điểm hơn ,vì sao ?

Fred: (waves to sarah) hi, i just moved here. my name is fred. sarah: hi fred. where are you from? fred: florida. the weather here in michigan sure is cold. sarah: i know what you mean, i moved here from san diego two years ago. wait until january. fred: i can just imagine. hey do you mind if i sit with you for a little while? sarah: no, take a seat. i’d love the company during lunch. fred: it’s been hard to meet anyone since i started school last week. sarah: no worries. i know exactly how you feel. i moved at the end of the school year and didn’t get to know anyone. then i spent the summer alone. fred: aw, bummer. it sure is tough to start a new school. sarah: yeah, but when school started again, i met some cool people. fred: i am really shy about meeting new people. sarah: well, i can introduce my friends to you. (bell rings) fred: that would be great! guess lunch is over. it’s been great talking to you. sarah: you too. meet me here for lunch tomorrow and i’ll introduce my friends. fred: great. bye. sarah: later. the conversation between fred and sarah is an example of impersonal communication. select the best answer from the choices provided t f

“unlike my opponent, i propose freedom from crime, freedom from poverty, and freedom from unemployment “ what rhetorical approach is the speaker most likely to be talking in this sentence? a. the speaker wants the audience to question the meaning of freedom and redifine it. b. the speaker wants the structure of this sentence to stand out in the listeners minds. c. the speaker wants to anticipate and address w counter-argument from his or her opponent. d. the speaker wants to transition into a topic that is largely unrelated to previous topics.

Besides the skull and cross bones what other shape sometimes appeared on flags flown by pirates?