In 1963,former Senator Gaylord Nelson began to worry about our planet (A senator is a person that the people of the United States have chosen to help make the laws.). Senator Nelson knew that our world was getting dirty and that many of our plants and animals were dying .He wondered why most people weren’t trying to solve these problems. He talked to other lawmakers and t
o the President. They decided that the President would go around the country and tell people about these concerns（关系重大之事）. He did, but still not enough people were working on the problem.
Then, in 1969, Senator Nelson had another idea. He decided to have a special day to teach everyone about the things that needed changing in our environment .He wrote letters to all of the colleges and put a special article in Scholastic Magazine to tell them about the special day he had planned
(Most of the schools got this magazine) and he knew that kids would help him.
On April 22,1970, the first Earth Day was held .People all over the country made promises to help the environment. Everyone got involved and since then, Earth Day has spread all over the planet. People all over the world know that
there are problems we need to work on and this is our special day to look at the planet and see what needs changing. Isn’t it great? One person had an idea and kept working until everyone began working together to solve it. See what happens when people care about our world?
小题1:The passage mainly talks about _________.
A．the importance of Earth Day
B．the person who planned the Earth Day
C．the history of Earth Day
D．the first Earth Day小题2:Why did Senator Gaylord Nelson worry about our planet?_________
A．The world was getting dirty.
B．Many plants and animals were dying.
C．Few people cared about the earth.
D．All of the above.小题3:From the text, we know that _________ helped him most .
A．the president
B．the other lawmakers
C．the colleges
D．the students小题4:It took Nelson ______ years to get the people pay much attention to the earth.
A．10
B．7
C．6
D．1
，则计算重锤下落的加速度的表达式
= 。(用
、
、
及
=_________________。