2. (20 points) We are sending a MP4 file of 500,000 bits from a source host to a destination host. All links in the path between source and destination have a bandwidth of 10Mbps. Assume that the propagation speed is 2.0108meters/sec, and the distance between source and destination is 10,000km. a) Initially suppose there is only one link between source and destination. Suppose the MP4 file is sent as one message, what is the transmit time? b) What is the total transfer time (transmit time plus propagation delay)? Page14 c) How many bits will the source have transmitted when the first bit arrives at the destination? d) Now suppose there are two links between source and destination, with one switch connecting the two links. Each link is 5,000 km long. Again, suppose the MP4 file is sent as one message. Suppose there is no congestion, so that the message is transmitted onto the second link as soon as the router receives the entire message. What is the total transfer time