4. What are the use cases for using the arrays and strings in the programs? List the available string library functions and their corresponding use cases. Write a C program to remove a requested character in the given test string and replace the empty space by a given character. Marks 25 5. Write a C program that can allocate and deallocate a two dimensional integer type of array. Draw the memory space occupied (e.g. stack, queue etc.) by the programs of 4,5. Marks 20 6. Discuss the concepts of merging arrays and pointers in the structure type design, definition. Marks 10 7. There are ip_adresses, protocols are stored in a file named as internet.txt file. You are asked to design a pipeline statement that can printout a particular segment of the ip adresses in the deceasing order. Explain the system commands, pipeline symbols that you will use to design the complete statement