How would you describe the distributions of the grades of students who did, and did not, attend

Question:

How would you describe the distributions of the grades of students who did, and did not, attend class in Figure 3.4? Why would you have expected this kind of even before you saw the data?
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...