Perimeter of yield will be perimeter of triangle (26*3=78 cm)+ perimeter of the three circles (3*2pir=6pir=9pi)=78+28.26=106.26
What will be perimeter of stop sign?

Won't it be 10*4*8=320 cm?

If it's an octagon, then perimeter is simply 8*10=80. The tricky part should be Quantity B, but I would argue it is D.

The perimeter of a polygon is found by adding up the lengths of all its sides, or multiplying the length of one side by the number of sides if all sides are of equal length. An 8-sided Stop sign with sides of 10″ length has a perimeter of P = ns = 8(10″) = 80″. An equilateral triangle has three sides of equal length, so this special Yield sign has a perimeter of P = ns = 3(26″) = 78″. Information regarding the reflectors attached the front of the sign is irrelevant and should be ignored, as perimeter is the measure of a shape’s exterior edges. 80″ > 78″, so the Stop sign has a greater perimeter and the answer is a.