A star is 8.1 × 1013 km away from the earth. Suppose light travels at the speed of 3.0 × 105 km per second. How long will it take the light from the star to reach the earth ?

A star is 8.1 × 1013 km away from the earth. Suppose light travels at

1.	A star is 8.1 × 1013 km away from the earth. Suppose light travels at the speed of 3.0 × 105 km per second. How long will it take the light from the star to reach the earth ?
A.	.5 × 103 hours
B.	.5 × 104 hours
C.	.7 × 1010 seconds
D.	.7 × 1011 seconds
Answer» C. .7 × 1010 seconds

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A star is 8.1 × 1013 km away from the earth. Suppose light travels at the speed of 3.0 × 105 km per second. How long will it take the light from the star to reach the earth ?

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