1. Suppose an engineer increases the number of possible signal levels from two to four. How many more bits can be sent in the same amount of time? Explain. 2. What is the bandwidth of a digital...

1. Suppose an engineer increases the number of possible signal levels from two to four. How many more bits can be sent in the same amount of time? Explain.

2. What is the bandwidth of a digital signal? Explain.

3. Why is an analog signal used to approximate a digital signal?

4. Why do some coding techniques use multiple signal elements to represent a single bit?