No Bass Amp

Ok, I myself have A Jcm 2000 Dsl 100 watt Marshall Half stack Guitar amp which i Play out of. And i have a PA system, a 750 watt/CHannel Power amp and a Behringer Sound Board and 2 500 watt 15" Yamaha Speakers, ANd i just bought a bass guitar for my friend and he is learning pretty fast and he is serious about this as I am. But the thing is we dont have a Bass amp as of now, can He play his Bass Through my PA without hurting it?. I dont want to blow out my speakers. Is there like a pedal he can plug into and then that goes straight to the soundboard? Also, how do i know how many watts are going to my speakers so I dont blow them out?

I think a bass pod would sort you out

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