如图所示，半径为0.4 m 的轮子绕中心点O匀速转动，边缘上的A _爱下问搜题

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问题计算题

如图所示，半径为0.4 m 的轮子绕中心点O匀速转动，边缘上的A 点线速度为6m/s，求轮子转过120 °角所用的时间t，及距O 点为1 m 的B 点在2s内通过的弧长s．

答案

；s=3 m

选择题

朝鲜战争是第二次世界大战后影响较大的局部战争之一。关于朝鲜战争爆发的原因至今仍是众说纷纭。你认为导致出现这种情况的主观原因可能是（）

①事件本身复杂②作者立场不同③受意识形态制约④舆论混淆视听

A．①②③④

完形填空

In 1971, a young man who grew up very poor was travelling across the country, trying to make a new __36__ for himself. Along the way, he had __37__ run out of money and was forced to spend the night in his car. This    38    until one morning, after a week of sleeping in his car, he walked    39    into a restaurant and ordered a big breakfast.
After eating his first good meal in    40  , he found himself    41  to the waiter, telling him he had lost his    42 . The waiter, who was also the owner, walked    43   the chair where the young man had been sitting. He bent down,   44    a $20 bill that looked    45  it had fallen on the floor and said, “Son, you must have    46  this,” the owner said. The young man couldn’t believe his    47  ! He quickly paid for the breakfast, left a    48 , bought gas with the change, and headed West.
On the way out of town, he began to understand    49  the fellow did. Maybe nobody dropped the money    50  . “Maybe that fellow just knew I was    51  and he helped me in a way that didn’t __52__ me.” Right then he made a promise to help others if he could.
Later, he worked very hard and became a rich man. Now, he lives near Kansas City. Each year he    53   thousands of dollars. He is known as the “Secret Santa” because at   54  time each year, he personally hands money out to those on the streets and at hospitals. “I’ve lived the story, so I know it certainly more blessed（带来快乐的） to give than to ___55__, because it comes back to you many many times over,” he says. “It restores some faith in humanity.”

A．unexpectedly

D．necessarily

小题14:A. what B how C. where D. that