Answer:
A: area of one additional plan exceeds 624 square feet ...... it does not
Explanation:
let's lay out the six additional plans:
plan width length area
6 26 24 624
7 28 22 616
8 30 20 600
9 32 18 576
10 34 16 544
11 36 14 504
A: one additional plan (plan 6) does not exceed 624. so this incorrect
B: one of the plans (plan 11) is less than 544. this is correct.
C: area of plan 6 = area of plan 5. this is correct.
D: Plan 7 area (616) is less than area of plan 6 (624). this is correct.
So, A is incorrect