Answer:
the answer is: A 686 square inches
Explanation:
you have to find the area of the 1 rectangle
Area = lw
A= (21 in) (7 in)
= 147 in square
there are 4 rectangular faces so you will need to multiply by 4 to get a total of 588 square inch.
then take 1 congruent squares= 7 in. x 7 in. = 49 square inch
multiply 49 square inch by 2 to get 98 square inch
Find the total surface area of the rectangular prism, add all 4 rectangular faces to the area of the 2 square faces
588 square in + 98 square in = 686 square inches