## Abs

### Instructions

Create a function named `isPositive` that takes a number as a argument, returning `true` if the number is strictly positive, and `false` otherwise.

Create a function named `abs` that takes a number as an argument and returns its absolute value. You must make your own implementation. You **must not** use `Math.abs()`.

### Notions

- [Functions](https://nan-academy.github.io/js-training/examples/functions.js)
- [Ternary](https://nan-academy.github.io/js-training/examples/ternary.js)
- [Math.abs](https://devdocs.io/javascript/global_objects/math/abs)

### Code provided

> The provided code will be added to your solution, and does not need to be submitted.

```js
Math.abs = undefined
```
