Please write below functions in Haskell Programming Language remember to include both the (1) function declaration, and (2) function definition and use a multi-line comment at the top of each function.

I. Write a function sum that that uses recursion to compute the sum of all numbers from I to n. sum Integer > Integer 2. Write a function integersqrt that returns the integer square root of a positive integer n. The integer square root is defined to be the largest integer whose square is less than or equal to n, i.e. the result of integerSqrt 15 is integersqrt:: Integer -> Integer 3. Incorporate into the above function definitions an error message that will be output if the function is called with a value that is less than or equal to 0 4. Write a function exponent that recursively computes the result of raising some base number, b, to some exponent, e. (cg. 28 64). You may not use the or operators you must use recursion. This function will only be called on an exponent value that is a whole number (an integer that is 0 or greater) exponent' : nteger - Integer - Integer