Look and write the words. 看图,写单词。
cake, cookie, ice cream, kite, egg
用显微镜观察物体时,所用的目镜上标有“10×”,所观察到的物体被放大了150倍,那么使用的物镜上应标有 [ ]
A.10×
B.15×
C.5×
D.140×
The preferred agent used in fighting a helicopter crash fire is().
A.CO2
B.dry chemical
C.water
D.foam