Haskell - Functions with numbers P77907

In this problem you have to implement several functions in Haskell. You do not need to ask permission to write auxiliary functions, of course you can!

1. Write a function absValue :: Int -> Int that, given an integer, returns its absolute value.

2. Write a function power :: Int -> Int -> Int that, given an integer $x$ and a natural $p$, returns the$p$-th power of $x$, that is, $x^p$.

3. Write a function isPrime :: Int -> Bool that, given a natural, tells whether it is a prime number or not.

4. Write a function slowFib :: Int -> Int that returns the $n$-th element of the Fibonacci sequence using the recursive algorithm that defines it ($f(0)=0$, $f(1)=1$, $f(n)=f(n-1)+f(n-2)$ for $n\ge 2$).

5. Write a function quickFib :: Int -> Int that returns the $n$-th element of the Fibonacci sequence using a more efficient algorithm.

Scoring

Each function scores 20 points.