An accounting professor is notorious for being stingy in giving out good letter grades. In a large section of 85 students in the fall semester, she gave out only 4% As, 17% Bs, 49% Cs, and 30% Ds and Fs. Assuming that this was a representative class, compute a 90% confidence interval of the probability of getting at least a B from this professor. Use Table 1. (Round intermediate calculations to 4 decimal places, "z" value to 2 decimal places, and final answers to 3 decimal places.)
