The testbench should include stimulus generation and functional coverage. The testbench should not include response evaluation. That is, you do not need to check that the system responses are correct. All you need to do is generate the correct test stumulus and create coverage groups to detect that all interesting conditions have occurred.

You should generate test stimuli for test cases 4.1, 4.2, 5.1, and 5.3 in Tables 7.2 and 7.3 of the book. Do not make test stimuli in a completely deterministic way. Some inputs will be deterministic but more will be random, probably constrainted random. Add constraints to fit the test cases that you are writing.

In your solutions you will need to prove to me that your test stimuli have adequately satisfied test cases 4.1, 4.2, 5.1, and 5.3. In order to prove that each test case is satisfied, you will need to make a set of coverage groups for each test case and show that all coverage bins are hit at least once during testing. Defining the coverage groups for each test case is an important part of this problem set.