Final answer:
A(0) equals 90 square inches, as any number raised to the power of 0 is 1, and the initial area (before folding) is 90 square inches.
Step-by-step explanation:
The answer to the question 'A piece of paper is folded into thirds multiple times. The area A of the piece of paper in square inches after x folds is given by A(x) = 90 * (1/3)^x. What is A(0)?' can be found by substituting 0 for x in the given function. When x is 0, the expression (1/3)^x equals 1 because any number to the power of 0 is 1. Therefore, A(0) = 90 * (1/3)^0 = 90 * 1, which means A(0) = 90 square inches. The correct answer is C) A(0) = 90 square inches.