Is 68 times the speed of light as fast as a Greyhound?
It's about 1,000,000,000 times as fast as a Greyhound
The speed of a Greyhound is about 0.0000000670 times the speed of light.
(a.k.a. English greyhound) (approximate maximum speed)
Greyhounds reach average race speeds of 0.00000006710 times the speed of light. Despite their racing prowess, greyhounds are not considered energetic dogs — the typical greyhound race requires the dogs to run for less than 35 seconds.
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