A few questions to any explosives specialists or people that otherwise have any experience with hand grenades.

1. we have had a few incidents where low level gang members have been paid to throw hand grenades into people’s homes, supposedly through closed glass windows. How hard or easy is this? Is a hand grenade heavy enough - or has an appropriately sharp shape or the likes - to break the glass?
2. if one was hit by one of these attacks and one miraculously notices the grenade landing on one’s floor, is there anything that could be done to minimize physical damage to one’s body? Would, say, a piece of furniture shield one from the shards?
3. are the shards or the blast wave/pressure the more dangerous, or both?