anything over 18 degrees is considered a deep V ie your at 24 degrees, this cuts through waves, rather than slamming over them. this means deep v hulled boats are more comfortable in choppy / rough conditions. anything less is considered a medium V, generally down to 12 degrees, below that it is unlikely to be found on ribs intended for sea use.
while i was checking my info (it is over 6yrs since i studied boat design - grey cells diminishing) i also found this website that gives some info on boat design aspects- beware though its yankee doodle, so some terminology could be different.
boats can be constant deadrise ie. the same angle all along the hull, or variable / progressive deadrise in which case the deadrise increases towards the bow.