What levels are considered "good"... ie we start at 5 and are "babies" barely able to stand up to a wet handkerchief, we work up to X and are "fairly good" and fight off some local critters and perform basic tasks without fainting in seconds, when we get to Y we can consider ourselves "ok". When we get to Z we're "really quite good" and will find it's a real pain getting any further etc.
solve for x, y and z (I'm thinking "20's", "30's" etc not broken down by individual humor)