A:30°
B:45°
C:60°
D:120°
根据表格内容, 选择正确答案。
(B)
Wang Wei
I can't sing or dance. I can play the guitar. But I couldn't play it three years ago.
Alice
I can sing and dance. I can also play the piano. When I was six, I couldn't play the piano at all.
James
I can swim and cook. I can't draw pictures. I could swim when I was five years old.
Liu Fang
I can perform ballet and dance to disco. I can also sing English songs. But I couldn't sing English songs two years ago.
在探究凸透镜成像规律的实验中,当蜡烛、凸透镜、光屏在如图所示的位置时,光屏上得到一个清晰的像.下列光学仪器中,利用了这一原理的是( )
某商场的营业时间是8:30~22:30,全天营业时间为15小时。(判断对错)