please help me on this homework question, and also please provide an explaination on how to do it

2. (10 pts) Consider the following program fragment: void testO int ii int [5] a; void f (int x) ( a[i] = 5; i=i-1; =x; i=2; a[1] = 3; a[2] = 7; f (ai]) What are the values of i and a [2] after function f returns if the parameter is passed by i a [2] value copy-in-copy-out reference need