verilog basics and test bench

Question 4: Provide a short answer to the following questions (a) Why is it better to use a case statement over a nested if-else statement? (b) Suppose we assign A and B as shown in the code below. What are the waveforms of A and B? Assume that the value of A is 0, and the value of B is 1 when the code below is executed #5 A=1; #5 B 0; (c) Explain the difference in functionality between the--"and--=" operators