1. Given the function prototype void funl (int &, double) is the following function call valid or invalid? Why or why not? double x, y: fun1 (x, y) 2. Given the function prototype void funl (int &, double); is the following function call valid or invalid? Why or why not? double x, y: fun1 (static cast (x), 3); 3. Given the function prototype void funl (int &, double); is the following function call valid or invalid? Why or why not? int x, y: fun1 (x, y); 4. Given the function prototype void funl (int &, double); is the following function call valid or invalid? Why or why not? int x, y; double z; funl (x + y, z): 5. Given the function prototype double fun2 (int , double) is the following function call valid or invalid? Why or why not? double x, y: fun2 (x, fun2 (x, y) )