What is the ph of balsamic vinegar having an acetic acid content of 7%? Ka= 1.8x10^-5

Refer to the following information and answer the question based on the Ricardo model:
U.S. U.K.

Wheat (bushels/labor hour) 100 40

Cloth (yards/labor hour) 150 30

The U.S. has comparative advantage in:

a. Cloth.

b. Wheat.

c. Both Wheat and Cloth.

d. Neither product

What is the maximum vertical distance between the line y = x + 2 and the parabola y = x² for ?1 ? x ? 2?