Letter on position 1 (b) changed: 12 words dacks hacks jacks lacks macks packs racks sacks tacks wacks yacks zacks Letter on position 2 (a) changed: 3 words becks bocks bucks Letter on position 3 (c) changed: 5 words balks banks barks basks bauks Letter on position 4 (k) changed: 1 word bachs