Three Galaxies, Each of Mass M = 4

Multiple Choice

Three galaxies, each of mass M = 4.0 × 10⁴¹ kg, lie in a plane at the corners of an equilateral triangle with sides of 5.0 × 10²² m length. The magnitude of the force the other two galaxies exert on each galaxy is

A) 4.3 × 10²⁷ N.
B) 6.4 × 10²⁷ N.
C) 7.4 × 10²⁷ N.
D) 8.6 × 10²⁷ N.
E) 4.3 × 10²⁸ N.