What does this log?

const m = new Map();
m.set(1, "number");
m.set("1", "string");
const o = {};
o[1] = "number";
o["1"] = "string";
console.log(m.size, Object.keys(o).length);

1. 2 2
2. 1 1
3. 1 2
4. 2 1

A Map remembers the order its keys were added and always loops in that order.

1. True
2. False

What does this log?

const m = new Map([["x", 1], ["y", 2]]);
console.log(Object.fromEntries(m), [...m.values()]);

1. {1: "x", 2: "y"} [1, 2]
2. {x: 1, y: 2} [1, 2]
3. {x: 1, y: 2} ["x", "y"]
4. [["x", 1], ["y", 2]] [1, 2]

What does this log?

const apples = { name: "Apples" };
const prices = new Map([[apples, 500]]);
console.log(prices.get(apples), prices.get("apples"));

1. undefined 500
2. 500 undefined
3. undefined undefined
4. 500 500

If a class stores a private value with secrets.set(this, { pin }) in a WeakMap, code outside the class can read it as acct.pin.

1. True
2. False