Assume you want to transfer a file containing 500,000 bytes from one computer to another on a bus topology local network. Assume the two computers are a distance D apart, that the bus data rate is B bps, and each frame is P bits long, where 80 of these bits are occupied by the header and trailer information. Each frame of the file must be acknowledged with a 96-bit frame (2 data bytes) before the next is sent. The propagation speed on the bus is 2.5x108 m/s. Compute the total time necessary to transfer the file for the following values:

a) D = 100m, B = 1Mbps, P = 256 bits

b) D = 1km, B = 10Mbps, P = 512 bits

c) D = 100m, B = 40Mbps, P = 1024 bits

d) D = 1km, B = 100Mbps, P = 10,000 bits