a. What line(s) of code do you need to change to make the LED blink (like, at all)?
No lines need to be changed!
b. What line(s) of code do you need to change to change the rate of blinking?
We can change the delay parameter - lower the delay and the LED blinks faster.
c. What circuit element would you want to add to protect the board and LED?
A resistor would be good, to ensure the current does not exceed the limits.