On the homework, I used a symbol I didn't explain in class. On the third problem in the second section it looks like "60 raised to the power of 40", but the 40 is underlined. This means "60 fall 40", the falling factorial that shows up on most calculators as 60nPr40.
The fourth problem in the section section is "60 raised to the power of 40". On many calculators, the button that means "raise to a power" looks like ^, which is pronounced caret.
I will put up some examples of underflow and overflow on Friday.