The shown 10 Mbps bus transfers frames of 200 bits between nodes A, B and C using slotted Aloha. The signal propagation speed over the bus is 200,000 km/s. distance beetween A to B is 2km and B to C is Km 1. Find the vulnerable period of this system. 2. If each node usually generates 0.75 frames in each frame-transmission duration, what is the throughput of system? 3. If two frames sent by A and B collide, and each of them picks a random backoff time uniformly from 1 to10 slots, what is the chance that both frames collide again? 4. Now, if a new bus is installed to increase the bit rate to 40 Mbps, should slotted Aloha still be used compared to other random access schemes? Justify your answer numerically. 5. After cable replacement, a TDM-based reservation scheme is used such that nodes can do 2-frame reservation in each reservation period. If the reservation mini-slot duration is 5% of the duration of a frame transmission, what is the maximum throughput of this system?