109. Solve each of the expressions for x using the quadratic formula and the x is small approximation. In which of the following expressions is the x is small approximation valid? a. x/(0.2-x) = 1.3 x 10 b. x/(0.2-x) = 1.3 c. x/(0.2-x) = 1.3 x 10- d. x/(0.01 x) = 1.3 x 10-4