Consider the figure below, in which a single router is transmitting packets, each of length L bits, over a single link with transmission rate R Mbps to another router at the other end of the link.

Suppose that the packet length is L$=4000$ bits, and that the link transmission rate along the link to router on the right is R $=1000$ Mbps$.$

What is the maximum number of packets per second this link can transmit?