script.js

function foo(role, level) {
  console.log(`Your role is ${role} and your level is ${level}.`);
  console.log(this);
}

foo();

var person = {
  name: 'Julie'
};

foo.call(person, 'developer', 'pro');
foo.apply(person, ['developer', 'pro']);

const whoIs = foo.bind(person);

whoIs('developer', 'pro');

function multiply(a, b) {
  return a * b;
}

const double = multiply.bind(null, 2);
console.log(double(3));