The speed limit on some interstate highways is roughly 100 km/h. (a) What is this in meters per second? (b) How many miles per hour is this?

Richard is driving home to visit his parents. One hundred forty (140) mi of the trip is on the interstate highway where the speed limit is 65 mph. Normally Richard drives at the speed limit, but today he is running late and decides to take his chances by driving at 73 mph. How many minutes does he save?

1.8. While driving in an exotic foreign land, you see a speed limit sign that reads 180,000 furlongs per fortnight. How many miles per hour is this? (One furlong is g mile, and a fortnight is 14 days. A fur- long originally referred to the length of a plowed furrow.)

The average distance between Earth and the Sun is 1.5 x 10¹¹ m.

(a) Calculate the average speed of Earth in its orbit (assumed to be circular) in meters per second. (b) What is this speed in miles per hour?