单项选择题

A．Because the Earth is heavily polluted.
B．Because nature cannot recycle its resources.
C．Because there are more and more people living on the Earth.
D．Because no more new resources can be added.
<上一题 目录 下一题>
热门 试题

单项选择题
A．About 80 miles per second.B．About 70 miles per second.C．About 18 miles per second.D．About 17 miler per second.
A．About 80 miles per second.
B．About 70 miles per second.
C．About 18 miles per second.
D．About 17 miler per second.
单项选择题
A．Because both have a limited supply of air, water, and other resources.B．Because the Earth moves around the sun as fast as a spaceship.C．Because we can travel to outer space.D．Because the Earth never stops moving.
A．Because both have a limited supply of air, water, and other resources.
B．Because the Earth moves around the sun as fast as a spaceship.
C．Because we can travel to outer space.
D．Because the Earth never stops moving.
相关试题