Take a look at the following code:

1    let x = 1;
2    function f1()
3    {
4        let x = 2;
5        console.log(x);
6    }
7    console.log(x);

Explain why line 4 and line 6 output different numbers. The first console.log(x), gives 2 because x has been declared in the function scope. The second console.log(x), gives 1 because x has been declared as a global scope.

Take a look at the following code:

let x = 10

function f1()
{
    console.log(x)
    let y = 20
}

console.log(f1())
console.log(y)

What will be the output of this code. Explain your answer in 50 words or less.

The output of console.log(f1()) is 10, because x has been declared in a global scope and therefore when the function has logged outside the function, we can see the output. The output of console.log(y) is undefined, because y has been declared in a function scope and therefore it can not be accessed out of the function.

Take a look at the following code:

const x = 9;

function f1(val) {
  val = val + 1;
  return val;
}

f1(x);
console.log(x);

const y = { x: 9 };

function f2(val) {
  val.x = val.x + 1;
  return val;
}

f2(y);
console.log(y);

What will be the output of this code. Explain your answer in 50 words or less. The out put will be 9 and 10.