The speed limit on some interstate highways is roughly 80 km/h. what is this in meters per second? how many miles per hour is this?

1) Speed in m/s equals 22.22 m/s.

2) Speed in miles per hour equals 49.712 mph.

Explanation:

Since we know that in 1 kilometer there are 1000 meters and in 1 hour there are 3600 seconds hence we can write

Now we know that 1 mile equals 1.609 kilometer  hence we conclude that 1 kilometer equals mile

Hence