反映自然对流的流动状况对对流传热过程影响的数群是
A. 努塞尔数
B. 雷诺数
C. 普朗特准数
D. 格拉晓夫数
How did the speaker keep her friendship with the girl who laterbecame her college roommate?
A. By using Facebook.
By writing letters to each other.
C. By talking over the phone often.
D. By meeting each other regularly.
Why does she love social media?
A. She can make more friends.
B. She can learn new knowledge.
C. She can post photos to show off.
D. She can express herself by creating posts.
What example is used when the speaker talks about social mediamarketing?
A. “Longest Short Story Ever” event.
B. Her friendship with a girl.
C. Funny, relevant or inspiring posts.
D. Facebook in her college life.
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