Transmission Delay

A two-port bridge connects on end of cable of length X m. to on end of a similar cable of length 3x/2 m. Hosts are attached at various points on the cable system, which operates as a shared-access LAN implementing the CSMA/CD protocol with a minimum frame length of 512 bits.  The bridge imparts a delay in forwarding frames that is equal to a time duration (transmission delay) of a frame. Assume a bit rate of 100 Mbps on the cable, and a propagation speed of 2.5 x 10^8 m/s
a. What is the minimum forwarding delay at the bridge?
b. What is the maximum allowable value Xmax of X?
c. The system is built with X-Xmax. An engineer argues that host on the sort side of the bridge can use a minimum frame length shorter than 512 bits if they are talking to other hosts on the same side.  Is he correct?