Ok, so I'm playing this game and have run into these riddles that for the life of me I can't solve. I figured since theres a bunch of smart guys here maybe someone has some ideas.

Here they are:

A H AA BL DU HH ME SR ?
AB+BC=AC, BC=BD=AB=AD, CD=87, AC=square root of ?
ls b sp cl h tcr oc bs ma lg q ?
AUCG - O equals ?