Can someone please help me out. Include some explanations PLEASE
(Label the ones you answered.)

first' term a= 11

second term = 26

so common difference = 15

n = 13

Sum = 13/2[22+180]

sum = 1313

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6