Rick and Mary are from America．Now they are working in Tianjin．They can speak a little Chinese．Every morning they get up very early．Then they go to work by car.·They are very busy．They have lunch at the factory．①After lunch they work again．They finish their work very late．  In the evening they take Chinese lessons(上汉语课)．They want to talk with Chinese people．They often say，“Chinese people are very friendly(友好的)．”②They like to stay in China and they like to work with Chinese people．

根据短文内容，完成下列题目。

cos600$°$=（    ）

There are many _______ in the mountains.

美国拥有许多世界一流的大学，研究电子计算机的人却对其中的情有独衷，因为世界上第一台电子计算机就是诞生在它的实验室，它是（   ）