/diy/ - Do It Yourself

This question is from the Art of Electronics, and I'm having a difficult time with it.
I need to add a collector resistor to this circuit, because the output voltage (the voltage across the emitter resistance) is 5 V, and then if I were to operate this in saturation, the V_CE would be something like 0.3 V. Therefore I need a collector resistor to drop 15-5.3 - 9.7 V.

I don't know the collector current, however, with my assumption of using the max emitter current, I can find it if I had a specific beta. The problem with this, I think, is that poor designs use beta as a determining parameter according to AoE. So, how should I choose a collector resistance?

Additionally, what is meant by
>Choose your resistor values so that the output voltage doesn’t drop more than 5% under full load.
Full load isn't defined in the question is it?