阅读理解。
The Beijing Olympic Games will have 21,880 torchbearers (火炬手) for the torch relay (火炬接力). It
is the biggest in the Games' history. Here let's know about some torchbearers.
◆ Luis Hone, 14, is from Colombia. He lives in Zhuhai, Guangdong Province. He moved to China with
his parents as a baby. "I can speak English, Chinese and Spanish. I love China, which has been my world
all my life," he said. "The torch relay is a good chance to improve the understanding between people of the
world."
◆ Sang Lan, 26, will complete the torch relay using her wheelchair. Sang's fingers are not agile (灵活的)
because of her injury (受伤). The IOC officials suggested adding framework (框架) to her wheelchair to
hold the torch. But she insists that she will hold the torch with her hands. "I believe if you put your heart
into something, you can solve any problem," she said.
◆ Liu Xuan, 17, is from Nanjing Foreign Language School. He is an energetic student. He enjoys various
sports including football, basketball, badminton and running. "It will be an honor to be a torchbearer," he said.
◆ Zhang Jie, 23, is a reporter with Guangzhou Daily. "Torch relay is a good way to let the world know
China better," Zhang said. "Tin very proud that I can be part of it."
(Teens Daily, Feb 21, 2008)
1. How long has Luis Hone been in China?
A. 5 years.
B. 10 years.
C. Less than 10 years.
D. More than 10 years.
2. Who comes from Jiangsu among these four torchbearers?
A. Luis Hone.
B. Sang Lan.
C. Liu Xuan.
D. Zhang Jie.
3. What can we learn from this article?
A. Zhang Jie is a reporter living in Zhuhai and working for Guangzhou Daily.
B. Sang Lan will hold the torch with her hands.
C Luis is a student in a foreign language school.
D. Liu Xuan can speak several languages.
×100% 
mol·L－1
mol·L－1＋c(H＋) 
×100%，故A错误；B、a g NH3的物质的量为
=
mol，溶液体积为VmL，所以溶液的物质的量浓度为
=
mol·L－1，故B不正确；C、V mL饱和溶液中n（OH-）=n（H+）+n（NH4+）=[c（H+）×10-3+b]mol，所以
，C正确；D、混合前后溶质的质量不变为ag，水的密度比氨水的密度大，即ρg·cm－3＜ρ水，等体积Vml混合，混合后溶液的质量大于2ρvg，所以混合后质量分数小于0.5ω，故D不正确．选C。