为了在中考的体育测试中取得好成绩,小雨同学每天都进行体育锻炼。(1)他先沿着200m长的跑道慢跑锻炼,从6:00到6:10共跑了12圈。他的平均速度大约是多少?(2)慢跑结束后开始跳绳。如果小雨的质量是60kg,他每次起跳高度约是5cm,那么他每跳一次需克服重力做功大约多少焦?(3)在中考的“1分钟跳绳”测试中,小雨同学跳了160次,而小明同学跳了100次。 试问:测试中,成绩好的同学做功一定多吗?说出你的理由。
---Lisa, don’t let ______ in. I’m too busy to see ______ all the morning. ---OK. I ______.
---This Math problem isn’t easy for Jack to work out, is it? ---_______. He is far better at Math problems than we expected.
The food cooked the day before yesterday ______ bad. Throw it away.
---Were your parents at home last night? ---No. _______ of us went to my uncle’s birthday party.
---Whose badminton racket is this? It looks nice. How much is it _______? ---Sorry, I don’t know.