Answer from cs61c-ck (Allen Lee 16583554) for Question 1
Arguments to functions are associated by the order of arguments in the function definition. For example, if we have a function called foo that takes two integers x and y,
int foo (int x, int y) { ... }
then a call to foo just as foo(1,2); behinds 1 to x and 2 to y.  In Verilog, however, the caller can decide which value goes to which parameter regardless of the order in the parameter list, by specifying the parameter's name in the function call, preceded by a dot.