Why did New Yorkers become more caring after 9/11?

Mary didn’t go to the party last night because she ______ the baby for her sister until 9:30. A: must have look after B: had to look after C: must look after D: has to look after

According to the speaker, why did the following events occur: After 9/11, the murder rate in New York City went down by 40 percent. The suicide rate went down. The violent crime rate in New York went down after 9/11. Even combat veterans of previous wars who suffered from PTSD said that their symptoms went down after 9/11 happened.

Python提供的与读取文件内容有关的方法有哪些（） A: read() B: readlines() C: readin() D: readline()

When will the plane probably take off A: At 8:30 a.m. B: At exactly 9:30 a. m. C: After 9:30 a. m.

Cathy didn't go to Tom's birthday party last night because she ______ the baby for her sister until 9:30. A: must have looked after B: would have to look after C: had to look after D: should have looked after

9、某公司签发一张汇票,上面注明“at 90 days after sight”,则这是一张()

Looking back a year later after the 9/11 attacks, The New Yorkers carried on without any swagger and joy.

中国大学MOOC: Looking back a year later after the 9/11 attacks, The New Yorkers carried on without any swagger and joy.

The sense of , that is a hallmark of the American Psyche", was after 9/11. A: invulnerability;shattered B: invulnerability;shaken C: vulnerability;shattered D: vulnerability; shaken