什么是环境？地球环境由哪几部分组成？

用科学记数法表示：-0.00002001=（     ）

I once experienced an unforgettable trip to Gloucester to see some of the world’s most beautiful and exciting animals in their own habitat(栖息地), the North Atlantic Ocean.

After a long trip by bus, we got on the ship. After a while, we stopped and everyone began to shout because we saw a humpback whale（座头鲸）. It was wonderful. Sometimes, whales came so close to the ship that you thought you could easily touch them.

While we were watching the whales, a guide was giving us some information about them, She told us that we saw only two kinds of whales- 50 foot humpback whales (singing whales) and 70-foot finback whales(the second largest whales on earth). She also said we could easily recognize a whale by its tail because every whale has a different kind of tail just like people have different fingerprints.

They all have names,and on this trip we saw “Salt” and “Pepper”, two whales named by a biologist and a fisherman. They were swimming toghter all the time.

I took twenty-seven photos,but it was very hard to take them because the whales were quick and stayed on the surface of the ocean just for a short time. It was really something. It was one of the chances that a person hardly ever experiences in life, but I had that chance.

小题1:This passage is mainly about _________________.

A an unforgettable experience in the forest

B an unforgettable trip to see some strange animals in the mountains

C a long trip on the ship

D an unforgettable trip to watch whales

小题2:Everyone on the ship began to shout because_____________.

A a whale came so close to the ship

B they saw a singing whale

C they saw a finback whale

D they could touch the whale

小题3:When they were watching the whales, __________________.

A some of them fed the whales

B they found several kinds of whales

C a guide told them something about the whales

D some of them took many photos and touched the whales

小题4:How can we recognize a whale?

A By its tail                B By its head

C By its neck               D By its eyes

什么是等离子弧？有哪些分类？

《全国人民代表大会和地方各级人民代表大会选举法》第53条规定：“省、自治区、直辖市的人民代表大会及其常务委员会根据本法可制定实施细则，报全国人民代表大会常务委员会备案。”这一规范属于( )。

A．委任性规范

B．授权性规范

C．非确定性规范

D．准用性规范

某化工企业依法申领了化学危险物品生产许可证，该许可证属于（）。

A、适用于各种影响环境的生产经营活动许可证

B、对环境有影响的建设项目的批准证书

C、适用于各种排放、处理、转移污染物活动的许可证

D、企业具备了生产化学危险物品的技术水平的资格证书