If the length and the breadth of a rectangle are doubled, then its perimeter

1. remains the same

2. doubles

3. becomes four times

4. becomes half

Let the length = l and the breadth = b.

Original perimeter = 2(l + b)

If length and breadth are doubled, new length = 2l and new breadth = 2b.

New perimeter = 2(2l + 2b)

= 2 × 2(l + b)

= 2 × Original perimeter

Thus, the new perimeter is twice the original perimeter.

Hence, option 2 is the correct option.