Consider Three Galaxies, Alpha, Beta and Gamma

Multiple Choice

Consider three galaxies, Alpha, Beta and Gamma. An astronomer in Beta sees each of the other two galaxies moving away from him in opposite directions at 0.70c. At what speed would an
Observer in Alpha see the galaxy Gamma moving?

A) 0.94c
B) 0.98c
C) 0.82c
D) 0.70c
E) 1.4c