Answer the following questions for the pxsrogram below: 1 #include 2 using namespace std;3...

Answer the following questions for the pxsrogram below: 

1 #include 
2 using namespace std;
3
4 class Parent
5 {
6 public :
7  void f()
8 {
9   cout <<"invoke f from Parent” << endl;
10 }
11 };
12
13   class Child: public Parent
14 {
15   public :
16  void f()
17 {
18   cout << "invoke f from Child"  << endl;
19 }
20 };
21
22 void p(Parent a)
23 {
24   a. f();
25 }
26
27   int main()
28 {
29   Parent a;
30   a. f();
31   p(a);
32
33   Child b;
34   b. f();
35   p(b);
36
37   return 0;
38 }

a. What is the output of this program?

b. What will be the output if line 7 is replaced by virtual void f()?

c. What will be the output if line 7 is replaced by virtual void f() and line 22 is replaced by void p(Parent& a)?