Determine the rhyme scheme of the following poem. xxvii (from fairie queene) by edmund spenser not that great champion of the antique world, a whom famous poetes verse so much doth vaunt, a and hath for twelve huge labours high extold, b so many furies and sharpe fits did haunt, b when him the poysond garment did enchaunt, with centaures bloud and bloudie verses charm'd; as did this knight twelve thousand dolours daunt, whom fyrie steele now burnt, that earst him arm'd, that erst him goodly arm'd, now most of all him harm'd.