Arrays and loops:

let classMarks = [62,88,90,70,69,85];
for (i=classMarks.length-1; i >= 0; i--) {
console.log(classMarks[i]);
} // outputs each element reversed
for (let number of classMarks) {
console.log(number);
} // outputs each element
classMarks.forEach(function(number) {
console.log(number+2);
}); // adds 2 to each number and outputs it
let counter = 0;

let j = 0;
while (counter <= 4) {
console.log(classMarks[j]);
counter ++;
j++
} // outputs the first 5 elements in the array