225.In the United States,vacationers account for more than half of all visitors to what are technically called "pure aquariums" but for fewer than one quarter of all visitors to zoos, which usually include a "zoo aquarium" of relatively most scope.
WHich of the following ,if true, most help to account for the difference described above between visitors to zoos and visitors to pure aquariums?
答案为B：Virtually all large metropolitan areas have zoos,whereas only a few large metropolitan areas have pure aquariums.
244. Critics of sales seminars run by outside consultants point out that since 1987,revenues of vacuum cleaner companies whose employees attended consult ant-led seminars were lower than revenues of vacuum cleaner companies whose employees did not attend such seminars.The critics charge that for vacuum cleaner companies,the sales seminars are ill conceived and a waste of money.
Which of the following ,if true ,is the most effective challenge to the critics of sales seminars?
答案为A:Those vacuum cleaner companies whose sales were highest prior to 1987 are the only companies that did not send employees to the seminars.
