Assume we have a digital signal propagating 1000 meter per second in a cable (propagation speed) and each bit last 2 milliseconds.

a. What is the bit length (the length a bit occupies in the cable) in meters (Note that length = speed * time)?

b. If the cable is 500 meters long, how many bits fill the cable when the first bit reaches the end of the cable?

Please elaborate the answer if you can, thank you.