10 - 10 is the correct answer.

Here’s what happens step by step:

1. a is assigned the value 10.
2. b is assigned the value of a, which is 10.
3. changeValue(b); is called, passing the value of b, which is 10, to the changeValue function.
4. Inside changeValue, param is assigned the value 3, but this does not affect the value of b outside the function.
5. const result = a + ' - ' + b; assigns the string '10 - 10' to result.
6. console.log(result) prints '10 - 10'.

So, the final output will be:

10 - 10

function changeValue(param) {
param = 3;
}

let a = 10;
let b = a;

changeValue(b);

const result = a + ' - ' + b;

console.log(result)

Correct answer is 10-10.

the correct answer is 10-5 not 10-10