Tickets for the World Expo (世博会) 2010 wi
问题：
Tickets for the World Expo (世博会) 2010 will go on sale for groups on March 27, and for the public on July 1, 2009.
The basic ticket price will be 160 yuan. Foreigners will be able to buy tickets from overseas outlets authorized （授权）by the Bureau of Shanghai World Expo Coordination (BSWEC).
From March 27 to June 30, group bookings can be made for organizations, institutions and enterprises. The public can buy tickets from July 1.
Peak day admission tickets will cost 200 yuan and will cover 17 days including Chinese Labor Day holiday (May 1-3), National Day holiday (October 1-7), and the last week before closing (October 25-31).
Tickets will be discounted（打折）from 10 to 30 yuan for those who buy before the Expo opens on May 1, 2010.
People going to the Expo after 5pm (apart from the peak days) can get tickets for 90 yuan but only during Expo.
Three-day passes will cost 400 yuan and seven-day passes 900 yuan.
At least 62 million tickets will be available. Discounts will also be offered to the disabled, senior citizens, students with valid IDs and Chinese servicemen and women. Children under 1.2 meters will not have to pay.
The basic price is “affordable” for the majority of people. It was common practice to set ticket prices within the 1 to 3 percent range of the host country's per-capita disposable income (人均可支配收入).
The Expo organizer will encourage people to reserve tickets in advance or buy group tickets in an attempt to control visitor flow. The organizer is expecting 70 million visitors, 5 percent of whom will be from overseas.
The organizer will appoint domestic and overseas agencies（代理） to sell tickets and there will be 3,200 sales outlets in China. People will be able to purchase tickets at branches of China Mobile, China Telecom, Bank of Communications and China Post. Online and hotline channels will also be opened.
The first domestic and overseas ticket sales agencies will sign contracts with the organizer on March 2.
During Expo, visitors will be able to buy tickets on site or at kiosks（电话亭）. The Expo Bureau will appoint travel agents to organize group tours.
49. If you want to visit Expo at 9 a.m. on May 2, 2010, you will have to pay ______ for the ticket.
A. 200 yuan B. 90 yuan C. 160 yuan D. 190 yuan
50. According to the passage, all these people can receive discounts EXCEPT __________.
A. senior citizens B. the disabled
C. Chinese servicemen and women D. students without valid IDs
51. To control visitor flow, the Expo organizer will__________.
A. sign contracts with the sales agencies
B. appoint travel agents to organize group tours
C. appoint domestic and overseas agencies to sell tickets
D. encourage people to book tickets ahead of time or buy group tickets
52. The main idea of this passage is__________
A. where people can buy Shanghai Expo tickets
B. that Shanghai World Expo will be held on 2010
C. that Shanghai World Expo tickets will set to go on sale
D. how people can buy tickets to visit Shanghai World Expo