a.Fiber optics are flexible,glass fibers.
b.Copper wires have been used in most phone systems.
c.Fiber optics are an improvement in communication systems.
d.A few optical fibers can carry thousands of phone calls.
2.As it is used in the passage,the phrase fiber optics means _____.
a.transmission of information by means of infra-red light signals aling a thin glass fiber.
b.material or substance formed from a mass of fibers.
c.a flexible fiber-optic instrument that is used to view objects
d.a composite material consisting of glass fibers in resin
3.Which of the following can not be inferred about fiber cables from the passage?
a.They carry light waves.
b.They can be used in many forms of communication.
c.They are better than copper wires.
d.They are shorter than copper wires.
4.You can infer from the passage that a cable is _____.
a.a group of wires or strands that are bundled together
b.a copper wire that is used to carry phone calls
c.a glass fiber that carrise coded bursts of light
d.a laser that changers electrical impulses into light
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