Consider sending a large file of f bits from host a to host b . there are four links (and three switches) between a and b , and the links are not congested (that is, no queueing delays). host a segments the file into segments of s bits each and adds 100 bits of header to each segment, forming packets of l = 100 + s bits. each link has a transmission rate of r bps. find the value of s that minimizes the delay of moving the file from host a to host b . neglect propagation delay.