Amps / Speaker Cabs / Ohms / Questions

For the electricians out there, I just got a new amp head. I have 2 cabs I’d like to hook up to it.

My 2x15 cab is 16 ohm

My 8x8 is 4 ohm.

There are 2 speaker jacks on the back of the Orange Bass Terror and an impedance switch for 4 or 8.

The Bass Terror has a tube preamp and a solid state power amp - it is 500 watts RMS.

Is there a way I can plug both cabs in without damaging anything? Is this Safety Town?

This has always confused me greatly.