1. (2 pts.) Given an amplifier with an effective noise temperature of 15,000 K and an 8MHz bandwidth, what thermal noise level, in dBW, may we expect at its output? 2. (2 pts.) Consider a noiseless channel with a bandwidth of 7 kHz transmitting a signal with four signal levels. What is the maximum bit rate, in bps, of this channel? 3. (4 pts.) Consider a channel with a 3 MHz capacity and an SNR of 255. a. What is the upper limit to the data rate that the channel can carry? b. The result of part (a) is the upper limit. However, as a practical matter, better error performance will be achieved at a lower data rate. Assume we choose a data rate of 2/3 as the maximum theoretical limit. How many signal levels are needed to achieve this data rate? 4. (2 pts.) Given a channel with an intended capacity of 50 Mbps, the bandwidth of the channel is 4 MHz. Assuming white thermal noise, what signal-to-noise ratio is required to achieve this capacity?