一个角是20°10′，则它的余角是​____ 

A：What do you want to be____?

B：____

A：Why? Many students don't like their teachers.

B：Because my grandma is a teacher. She is very friendly, and her students all love her very much.

A：I think____

B：Thanks. What about you?

A：____like Brad Pitt(布拉德•皮特).

B：Wow, he is very smart and cool. I like his films very much.

A：Yeah. ____these days. I hope my dream can come true one day.

B：Good luck!

 2013年12月15日，中国首辆月球车“玉兔号”顺利抵达月球表面。如图所示，“玉兔号”的车轮采用密度小、强度大的铝合金制造，而且轮子数目较多，其目的是为了____；轮的表面有很深的花纹，其目的是为了____。