题目内容
（请给出正确答案）
Are you thinking of writing someone a letter？ Call...
Are you thinking of writing someone a letter？ Call instead. It isn't that expensive, especially when you call during the evening, night, or weekend hours. In fact, you can make a ten-minute call anywhere in the continental United States for just $2.60. For even greater saving, always dial direct, that is, without an operator's help. Rates on direct calls are lower after five o'clock in the evening and lowest after eleven o'clock at night. Collect, person-to-person, and pay phone calls require the services of an operator, and they cost more than direct calls. Need to call out of the country？ Now calls to many overseas places may be dialed direct. Check your telephone direction for overseas area codes. Next time you have good news, or you just want to stay in touch, remember, a phone call means so much more than a letter. This has been a message from Southern Bell Telephone Company. 1. According to this passage, when is a dial telephone call cheapest？
A、After 11 at night.
B、After 5 in the evening.
C、During weekend hours.
D、During working hours.
E、Any time you want.
简答题官方参考答案
（由简答题聘请的专业题库老师提供的解答）
抱歉！暂无答案，正在努力更新中……
Refer to Figure 12.1. Six firms that produce chewing gum have formed a cartel. The cartel faces the market demand curve given by D. To maximize profits, the cartel should produce ________ packs of chewing gum and the price should be ________.
