Answer:
Star A
Explanation:
μ = proper motion = 1 arcsecond per year
r = 20 light-years = Distance
Transverse velocity
V = 1.45 × μ × r
⇒ V = 1.45 × 1 × 20
⇒ V = 29 km/sec
When r = 10 light-years
V = 1.45 × 1 × 10
⇒ V = 14.5 km/sec
∴ Star A which is 20 light-years from Earth is moving faster compared to Star B which is 10 light-years from Earth.