单项选择题

How is television different from radio

A．Sound is changed into electromagnetic waves.
B．Light is changed into electromagnetic waves.
C．Both sound and light are changed into electromagnetic waves.
D．Either sound or light is changed into electromagnetic waves.

<上一题目录下一题>

热门试题

单项选择题

The main purpose of the laptop program is to give each student a laptop to ______.

A．use for their schoolwork
B．get access to the Internet
C．work at home
D．connect them to libraries

单项选择题

Why did one Westlake teacher say they are giving students a window to the world

A．Because students can attend lectures on information technology in Westlake college.
B．Because students can travel around the world by the laptops there.
C．Because students can get information from around the world by the laptops there.
D．Because students Can have free laptops in Westlake college.