8. indexOf0 Without using the native Array.prototype.indexOf" method of JavaScript, compose a function titled myIndexOf that will take in an array of elements and returns the index of the first encounter of a target element (if it is found) or -1 if that element does not exist within the input array. 9. push() Without using the native "Array.prototype.push" method of JavaScript, compose a function titled myPush that will take in an array of elements as well as an elementToAdd and append that element to the end of the array. 10. lastIndexOf( Without using the native Array.prototype.lastIndexOf" method of JavaScript, compose a function titled myUnshift" (typo) that will take in an array of elements and returns the index of the last encounter of a target element (if it is found) or -1 if that element does not exist within the input array