In C programming, when you have an array `int a[] = {10, 20, 30, 40};` and a pointer `int *p = a;`, what is the difference in the output of `sizeof(a)` and `sizeof(p)` assuming a 4-byte integer and an 8-byte pointer?

When an array like `int a[5] = {1, 2, 3, 4, 5};` is passed to a function `void fun(int a[])`, what will `sizeof(a)` print inside the `fun` function, assuming a 4-byte integer?

Consider the C code: `int a[] = {5, 10, 15, 20}; int i = 0; a[i++] += 5; a[++i] += 10;`. What will be the values in array `a` after these operations?

In the C code `int a[] = {2, 4, 6, 8, 10, 12}; for (i = 0; i < 6; i += 2) { a[i+1] = a[i] + a[i+1]; }`, which elements of the array `a` will be modified and how?