Two Stars Are at Rest Relative to Each Other $68.7 \text { light-years }$

Multiple Choice

Two stars are at rest relative to each other.In their common rest frame,these stars are 90.0 light-years apart.If they are measured to be $68.7 \text { light-years }$ apart by the navigator of a spaceship traveling between them,how fast is the spaceship moving relative to these stars?

A) 0.646c
B) 0.604c
C) 0.558c
D) 0.505c