1. This program will allocate the memory of ---- bytes for pointer "ptr" (Assuming that integers occupy 4 byte) and explain why the output is so?

#include #include 

int main() {

 int *ptr; ptr = (int*) malloc(sizeof(int)*3); ptr = realloc(ptr,sizeof(int)*2); return 0; 

}

2. What is the output of the following program and why explain?

#include #include 

int main() {

 int *ptr; ptr = (int *) calloc(1,sizeof(int)); if (ptr != 0) 

 printf("%d ",*ptr); return 0; 

}

3. What is the output of the following program and explain why?

#include #include 

int main() {

 int *ptr; ptr = (int *) malloc(sizeof(int)); if (ptr != 0) 

 printf("%d ",*ptr); return 0; 

}

4. Can we increase the size of dynamically allocated array (to 40)? If yes, increase the size of P in the following program? Explain why?

#include #include 

int main() {

 int *p; p = (int*) malloc(20); 

 // WRITE YOUR CODE HERE