Answer:
A. 7pi>21
Step-by-step explanation:
7*pi=21.99
21.99>21
You could multiply again by 2 or long multiply by 2
PEMDAS
2.5x + 0.1x = 2.6x
2.6x - 0.01x = 2.59x
Step-by-step explanation:

468 seats is the answer.
26 x 18
or
13 x 2 x 9 x 2
both equal 468