Exercise3. Suppose there is a 40Mbps microwave link between a geostationary satellite and its base station on Earth. Every minute the satellite takes a digital photo and sends it to the base station. Assume the propagation speed of 2108 meters/sec and the distance between the satellite and Earth is 36000km. 1. What is the propagation delay of the link? 2. What is the bandwidth-delay product? 3. Let T denote the size of the photo. What is the minimum value of T for the microwave link to be continuously transmitting? Exercise4. Describe how an e-mail gets transferred from the sender to the receiver, including the architecture of e-mails. Illustrations are recommended, and make sure to explain each stage in detail - do not copy the whole textbook. Figure 2