The area of the circle by definition is given by:

For f (r) = 154:

Clearing r we have:

For f (r) = 616:

Clearing r we have:
Answer:
a reasonable domain for f (r) is:
7 <r <14
Isn't 2,351 the standardized form already?
there is word form: two thousand, three hundred fifty one
there is expanded form: (2* 1000)+ (3*100)+ (5* 10)+ (1* 1)= 2,351
-5+6 = 1. This is the answer. Thank you
The answer is A. I hope this helps, have a great day!