uppose two nodes, a and b, are separated by 20,000 kilometers and are connected by a direct link of 100 mbps. suppose the propagation speed over the link is 2.5 x 108 m/sec. consider sending a file of 100,000,000 bits from node a to node b. suppose the entire file is sent continuously as one large message. what is the maximum number of bits that will be in the link at any given time?