Elements of objects can be changed by accessing them by keys. Let's see how it's done. Let's have the following object:
let obj = {a: 1, b: 2, c: 3};
Change the value of its element:
obj['a'] = '!';
Let's use property access:
obj.b = '!';
Check if the object has changed:
console.log(obj);
Given an object:
let obj = {x: 1, y: 2, z: 3};
Square each element of this object.