I need information on RCA home stereo speakers model 12A99, where do I go?

Question

they are three way speakers 8 ohms. Why is it that the tweeters are rated 8 ohms, the midrange rated 6 ohms, and the woofer rated 7ohms.? how can this be?

Answer 1

In simple terms...

The crossover in the speaker (the little PCB) will make it an 8 ohm load in the way that the three drivers are connected and filtered.

Impedance isn't resistance despite the fact it is measure in ohms - it's a function of capacitance, resistance and inductance. The crossover's components will have also impedance of their own.