短文填空 先通读下面的短文，然后根据短文内容和所给首字母，在空格内填入一个适当的词，使短文意思完整。所填单词必须在答题卡标有题号的横线上完整写出。（本大题共6分，每格0.5分）

Who was Leonardo da Vinci? You may answer without t    小题1:    : “He is the painter of the Mona Lisa.” What e    小题2:  do you know about him? Da Vinci was more than just a great artist in history. He’s also f   小题3:     as a scientist and an inventor.

Leonardo da Vinci was b    小题4:   to a rich family in Florence, Italy, in 1452. From childhood, Leonardo was given a good e   小题5:     and he showed talent at painting. By the age of 26, da Vinci had already become a famous painter.

He designed many i    小题6:    machines. Da Vinci’s idea l  小题7:    to the modern tank(坦克). Though da Vinci never b    小题8:     many of the inventions he designed, some of the things he i    小题9:    in the late 1400s are in use today.

As a scientist, da Vinci was very interested in the h小题10:   body. He spent a whole year c 小题11: up dead bodies in hospitals to learn about human anatomy(解剖学). He made more than 200 d 小题12:   of bodies.

热流密度是（）的性能指数。

A.冷却塔

B.水垢

C.换热器