台湾包裹办理“航空”、“空运水陆路”及“水陆路”业务的邮件。
参考答案：错
A ______ is used to communicate with another computer over telephone lines.
A．keyboard
B．modem
C．mouse
D．printer
There is a 30% chance that the economy will be good and a 70% chance that it will be bad. If the economy is good, your returns will be 20% and if the economy is bad, your returns will be 10%. What is your expected return（）
A. 15%.
B. 17%.
C. 13%.
