const promise1 = Promise.resolve(10);
const promise2 = promise1.then(x => x * 2);
const promise3 = promise2.then(x => {
  console.log(x);
  return x + 5;
});
const promise4 = promise2.then(x => {
  console.log(x);
  return x * 3;
});
Promise.all([promise3, promise4]).then(results => {
  console.log(results);
});