1.Harry Potter is mentioned in the passage,because scientists

A.can now make an invisible cloak of the same kind as he uses.

B.try to make an invisible cloak of the same kind as he uses.

C.try to invent a device Similar in idea to the invisible cloak he uses.

D.know that it is possible to make an invisible cloak of the same kind.

2.What is true of microwaves?

A.Their wavelengths are shorter than those of visible light.

B.Their wavelengths are longer than those of visible light.

C.They are different from visible light as they are a kind of radiant energy.

D.They are visible to the human eye.

3.What is NOT true of the invisibility device?

A.It is made of a special material with unusual ability.

B.Microwaves bounce off it when they strike it.

C.Microwaves pass through it when they strike it.

D.It bends the microwaves all the way around until they reach the opposite side.

4.What does the word"coaster"mean in the passage?

A.A disk or plate placed under a drinking glass to protect a table top.

B.A vessel engaged in coastal trade.

C.A roller coaster.

D.A resident of a coastal area.

5.Harry Potter's invisibility cloak doesn't have any real competition yet, because               . 

A.scientists have not found out how his cloak works.

B.the cloaking device is a total failure.

C.the cloaking device works only for microwaves.

D.the cloaking device works only for visible light.
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