Question 2 (8 marks total) (a) Two stations are connected by a communication link with a data rate of 1 Mbps, probability of bit error of 10*, and one-way propagation delay of 0.5 ms. A 1,000,000 bytes file is to be sent from one station to another in 1000 equal-sized packets. Using Selective Repeat ARQ, determine the total average time required to transmit the whole file. Assume the processing time, number of overhead bits and transmission time for ACKs are negligible. (5 marks) (b) Briefly explain the concept of code division multiple access