An art history professor assigns letter grades on a test according to the following scheme.
A: Top 13% of scores
B: Scores below the top 13% and above the bottom 56%
C: Scores below the top 44% and above the bottom 21%
D: Scores below the top 79% and above the bottom 9%
F: Bottom 9% of scores
Scores on the test are normally distributed with a mean of 79.7 and a standard deviation of 8.4. Find the numerical limits for a B grade. Round your answers to the nearest whole number, if necessary.