Given three sections of code. You need to write the result of each console.log. var n = 1; function f(n) { n = 3; } f(n); console.log(n); // ?? // ------------------ var obj = { a: 1 }; function f1(o) { o.a = 5; } f1(obj); console.log(obj); // ?? // ------------------ var obj = { a: 1 }; function f2(o) { o = { hello: 1 }; } f2(obj); console.log(obj); // ??

js var n = 1;

function f(n) { n = 3; } f(n);

console.log(n); // 1

Here, the parameter `n` of the function `f` is a local copy of the value passed during the call. Changing `n` inside the function does not affect the external variable.

```js
var obj = { a: 1 };

function f1(o) {
  o.a = 5;
}
f1(obj);

console.log(obj); // { a: 5 }

Objects are passed by reference, so changing a property of the object inside the function affects the original object.

var obj = { a: 1 };

function f2(o) {
  o = { hello: 1 };
}

f2(obj);

console.log(obj); // { a: 1 }

Here, the variable o inside the function is assigned a new object, but this does not change the reference obj outside the function. Therefore, obj remains unchanged.