a) We have been given two similar figures and we have to find ratio of perimeters of these figures.
Let a be given side of larger figure and b be the given side of smaller figure. Let
be the perimeters of two figures and
be the areas of the two figures.
We know that perimeters of two similar figures are in the ratio of corresponding sides.

We have been given,

Therefore, upon substituting these values in the above equation, we get


(b)
Further we know that areas of two similar figures are in the ratio of squares of corresponding sides.

Therefore, first option is the correct answer.