5 颗豆豆
1. 单选题
20 秒
Which of the following is greenhouse gas?
CO2
CH4
N2O
all the above
2. 单选题
20 秒
Which doesn't cause global warming?
smoke from vehicles
cutting trees
burning coal
use water energy
3. 单选题
20 秒
How does global warming happen?
the sun gives out much heat
greenhouse gases trap the heat
too many greenhouses are built
it is a natural thing
4. 单选题
20 秒
Which one fits the effects of global warming?
lower sea level
flood
drought
both B& C
5. 单选题
20 秒
What is renewable energy?
a newly discovered energy
a limited energy
it can be reproduced by itself
it produces greenhouse gases