please answer the above three questions using C language

7. Write a function in 'C to check whether a given string is palindrome or not. (If the string and its reverse are same, the string is said to be palindrome). Do not use any in-built string manipulation functions to implement your function 8. Write a program in C" to draw a circ le of radius 5 cm. Colour the circ le with 'blue' colour. 9. Write a program to create and store an array and write functions to check: (a) the diagonal ee ments are all zero or not (b) the upper triangular elements of the array are all-zero or all non zero. (c) if the upper/lower triangular ele ments of the array are all-zero, store these elements in a one-dimensional array