Its is surprising that no one attempted this question for over a week.
As in all geometry problems, start with a diagram (shown).
Then we realize right away that AB=sqrt(8^2+2^2)=sqrt(68)=2sqrt(17)
BC=sqrt(4^2+1^2)=sqrt(17)
The perimeter is therefore twice the sum of AB+BC=2(2sqrt(17)+sqrt(17))
2(3sqrt(17))=6 sqrt(17) We can estimate sqrt(17)=4.125, so 6sqrt(17)=24.75 which is close enough to get the correct answer choice.
Have a good day.
