Th1细胞主要分泌的细胞因子（）。 A.IL-1 B.IL-2 C.IL-3 D.I

舞台上经常用喷撒干冰(固态二氧化碳)的方法制造白雾 以渲染气氛．对“白雾”的形成，小明的解释是：(1)干冰升华吸热使周围环境温度降低；(2)气态二氧化碳液化形成白雾。对以上解释中：                           （    ）

A．第一句话存在科学性错误

B．第二句话存在科学性错误

C．两句话都存在科学性错误

D．两句话都没有科学性错误

如果流量计长期处于某一流量下工作，则可采用（）作为基准点进行检定.

A.流量下限值

B.流量上限值

C.常用流量值

D.标准流量值

阅读理解。

     American Watersports

     Tuesday--Saturday

     Located on the beach of the Sea Gardens Beach Resort, there are fun things to rent for the whole

family. They offer rentals for kayaks, jetskis, and even parasails! Enjoy the water upclose or from a bird's

eye view! No matter what activity you're enjoying, be sure to protect yourself and your family from the

sun's powerful rays and apply plenty of sun block! 15th Street Boat Company

     Monday --Saturday

     15th Street Boat Company offers rental boats of all kinds. They're sure to have what you are looking for,

whether it's a small boat for a quick and simple outing or an extravagent boat with comfortable seats with a

stereo(立体声) and high tech navigation (导航).You can rent a boat for half a day, a couple days, or even

weeks at a time. If you want it, they've got it.It's fun for everyone!

     Coconut's Watersports 9 a.m.-5 p.m.Monday through Sunday

     Coconuts Water Sports is open 7 days a week for your convenience and offers tons of water fun for the

whole family.Jet ski activities last 30 minutes or 1 hour and can make stops along the way. You must be at

least 14 years of age to ride alone and can be as young as 3 to ride along with an adult.Everybody is required

to wear a life jacket and a license is required to operate the jet ski. Bathing suits and shorts are recommended.

     Jet Ski Tours of Miami

     Thursday-Sunday 10 a.m.-7p.m.

     Jet Ski Tours of Miami includes onsite parking, indoor restrooms, lockers, and life jackets for participants.

You may choose a one or two hour tour and each jet ski can hold up to 3 people. You must be at least 18

years old in order to ride. As long as you are accompanied by an adult, there is no age limitation for any

passenger. There is a restaurant nearby to eat at. The tour visits 6 different islands and passes by Bayside

and Hard Rock. You may even catch a glimpse of dolphins playing or a manatee resting in these fabulous

Florida waters.

1. What activity is convenient for the visitors to have lunch?

A. Jet Ski Tours of Miami

B. Coconut's Watersports

C. 15th Street Boat Company

D. American Watersports

2. To satisfy your son's curiosity about marine animals, you _______.

A. will rent a boat to ride with him.

B. prefer an extravagant (奢侈的) boat with comfortable seats with a stereo.

C. would like to prefer American Watersports to Florida waters.

D. can choose the tour to Bayside and Hard Rock.

3. If you like to sail a boat, you can _______.

A. go to the Sea Gardens Beach Resort

B. visit 15th Street Boat Company

C. choose Jet Ski Tours of Miami

D. go to Coconut's Watersports

4. To ride alone in the jet ski activities, _______.

A. you have to be at least 14 years old.

B. you can choose to wear a life jacket or not.

C. you must be over18 years old.

D. you have to be with parents.

2009年12月8日，哈尔滨市举行调整城市居民生活供水价格听证会，根据听证方案，此次哈尔滨市居民供水价格调整的理由是哈尔滨市新的水源地磨盘山水库存建成供水，供水成本大幅增加。听证会代表和广大市民积极参与，发表见解，公民的有序参与，从公民角度看，有下列意义（）。

①提高公民的权利意识与责任意识

②提高自身的政治素养和参与政治生活的能力

③促进政府机关的谦政建设

④体现公民在政治生活中的主人翁地位

A.①②③④

B.①③④

C.②③

D.①②④

原子吸收光谱仪的火焰原子化器主要由（）组成。

A、石墨管

B、雾化器

C、燃烧器

D、石墨炉