he speed of light in a vacuum is about 3.00 108 m/s how many kilometers a pulse from a laser beam travels in exactly 3.9 hours.

change 3.9hrs to seconds,multipy by the speed of light.

To find out how many kilometers a pulse from a laser beam travels in exactly 3.9 hours, we can use the formula:

Distance = Speed × Time

First, let's convert the speed of light from meters per second to kilometers per hour:

Speed of light = 3.00 × 10^8 m/s

To convert meters per second to kilometers per hour, we need to multiply by the conversion factor:

1 kilometer = 1000 meters
1 hour = 3600 seconds

So, the speed of light in kilometers per hour is:

Speed of light = (3.00 × 10^8 m/s) × (3600 s/1 hour) × (1 km/1000 m)

Now, let's calculate the distance traveled by the laser pulse in 3.9 hours:

Distance = Speed of light × Time

Distance = (3.00 × 10^8 km/h) × (3.9 hours)

Now, we can calculate the final answer by performing the multiplication:

Distance = 3.00 × 10^8 × 3.9 km

Therefore, a pulse from a laser beam would travel approximately 1.17 × 10^9 kilometers (or 1.17 billion kilometers) in exactly 3.9 hours.

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