Roon ARC downloads - audio playing options away from home

If using Roon ARC I download music on my Apple device before leaving my house/Roon core.

Once over to my friends house :

Can I stream from Roon ARC to an AirPlay capable audio device ?
Can I stream from Roon ARC thru my friend’s Roon Core ?

If yes on either - what would be the best music download quality on either ?

Thanks