单项选择题

Which sound can most people's ears pick up（）

A．Sounds of 15,000 hertz.
B．Sounds of 20,200 hertz.
C．Sounds of 30,000 hertz.
D．Sounds of 50,000 hertz.

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单项选择题

When customers enter the store in the USA, they will （）

A．see store clerks sitting around watching TV
B．receive warm greetings from clerks
C．show their respects to clerks
D．be given a pamphlet introducing the goods

单项选择题

Why do people in the USA. feel shopping is a breeze（）

A．The price is very cheap.
B．The products are good.
C．The signs of departments are clear.
D．The departments are large.