19. An astronaut in a spaceship traveling at 0.64c passing just above a bridge, parallel to the length of the bridge, measures the length of the bridge over a river on earth nearby to be 146 m. The real length of the bridge is:
(A)130 m
(B)170 m
(C)190 m
(D)210 m
(E)None of the above
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統計: 尚無統計資料