New York and other U.S. cities have begun using vehicles powered by natural gas

中国大学MOOC: IIHere’s a paragraph that has both factsand opinions.Read and decide whether they are factsor opinions. (10 points, five for each)New York and other U.S. cities have begun using vehicles powered by natural gas[1]. This is a good idea[2], because vehicles that use natural gas do not pollute the air[3]. Pollution is the biggest problem facing cities right now[4]. Furthermore, natural gas is more cost-effective than regular gas[5]. All cities should use only vehicles powered by natural gas[6].1.Facts are _________

If you smell gas, ______ the gas, leave the house, and call the gas company.

42. According to the relevant regulation, lifeboat should be powered by _______.

A Popularity and use of natural gas B Natural gas reserves and supply C Natural gas prices D Clean fuel of choice E Disadvantages of natural gas F Natural gas consumption Paragraph 2______

What is the main advantage of electric cars over gas-powered cars A: They are cheaper. B: They do not pollute as much. C: They are simpler to drive. D: They are faster.

砷盐检查古蔡法中，中国药典规定砷斑为（）。 A: 1.0μgAs B: 1.5μgAs C: 2.0μgAs D: 2.5μgAs

When<br/>some fruits emit (),<br/>it causes other fruits to ripen. A: ammonia<br/>gas B: oxygen<br/>gas C: ethylene<br/>gas D: nitrogen<br/>gas

The role and position of unconventional oil and gas resources in global oil and gas production are becoming more and more important. Which of the following are unconventional oil and gas resources? A: Tight rock oil and gas B: Mud shale oil and gas C: Coalbed methane D: Oil shale E: Oil sands F: Natural gas hydrate

__________ is natural gas that is found trapped within shale formations. It has become an increasingly important source of natural gas in the United States since the start of this century. A: Methane B: Shale gas C: Coal gas