Not many people know because it hasn't happened, but i would say it would kinda be a mixture of a огонь and guts flying everywhere, like the zombie rick first saw, and the огонь at the farm. Hope I helped :)
Yes, technically. It would be noisy which would just draw more, so it's not the smart thing to do. There's also a possibility that the bomb won't blow their brains out, and if that happens, some of them might be alive.