Atrapezoid in which the legs are congruent, both pairs of base angles are congruent, and the diagonals are congruent is called

the answer is b: 18

step-by-step explanation:

use the pythagorean theorem to .

a^2+b^2=c^2

plug 18 for "r"

the 2 legs are 18 and 24

18^2+24^2=c^2

324+576=c^2

900=c^2

c=30

30-12=18

18 is the radius

: )

so mark-up is 0.4 multiplied by 180 = 72

the answer is  

c.

14,469 cubic feet

i know this one is right