Ballast resistor question ??

I forget stuff real quick, no big deal.
My head leaks knowledge almost as fast as I put it in, so it is in a constant state of filling and leaking. I have to read/see, the same stuff over and over, until it finds something to stick to; then finally, it becomes a building block. I got no desire to keep track of who said what when, or keeping score. With me every day is a start-over day. It's a good thing I don't have to sleep much anymore.