阿摩線上測驗
7. The production of glass fibers was
improved in the nineteenth century by
which of the following
(A) Adding silver to the molten glass
(B) Increasing the circumference of the
glass tubes
(C) Putting silk thread in the center of the
fibers
(D) Using yam reels
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統計： A(0), B(2), C(7), D(6), E(0) #803556
統計： A(0), B(2), C(7), D(6), E(0) #803556
