Consider three galaxies, Alpha, Beta and Gamma. An observer in Beta sees the other two galaxies each moving away from him in opposite directions at speed 0.7c. At waht speed would an observer in Alpha see the galaxy Gamma moving?
A、0.94c;
B、1.4c;
C、0.82c;
D、0.98c
发布时间：2025-07-26 05:41:27
