問題詳情

【題組】4. How much of the power consumed by incandescent bulbs is converted into light?
(A)A small portion.
(B)Some 40 percent
(C) Almost half.
(D) 75 to 80 percent.

參考答案

答案：A
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)