Files: a. Write a C program to display the contents of a file to standard output device. b. Write a C program which copies one file to another, replacing all lowercase characters with their uppercase equivalents. c. Write a C program to count the number of times a character occurs in a text file. The file name and the character are supplied as command line arguments. d. Write a C program that does the following: It should first create a binary file and store 10 integers, where the file name and 10 values are given in the command line. (hint: convert the strings using atoi function) Now the program asks for an index and a value from the user and thevalue at that index should be changed to the new value in the file. (hint: use fseek function) The program should then read all 10 values and print them back. Write a C program to merge two files into a third file (i.e., the contents of the first file followed by those of the second are put in the third file).