40. 目前公認的光速是 (A)3×1010m/sec(B)3×108m/sec(C)3×108mm/sec(D)3×108km/sec。

問題詳情

40. 目前公認的光速是
(A)3×1010m/sec
(B)3×108m/sec
(C)3×108mm/sec
(D)3×108km/sec。

參考答案

答案：B
難度：簡單0.717949
統計：A(2),B(28),C(8),D(1),E(0)