Multiple Choice
A giant star in another galaxy exploded 67 million years ago,forming a supernova.The event is observed by an astronomer on Earth.Estimate the speed at which the supernova (and its galaxy) recedes from Earth if the Hubble constant is 22 km/s per million light-years. 
,1 ly = 9.461 × 1015 m,1 y = 3.156 × 107 s)
A) 1200 km/s
B) 670 km/s
C) 1500 km/s
D) 2700 km/s
E) 4700 km/s
Correct Answer:
Verified
Correct Answer:
Verified
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