How will that compare to the number who would buy the same product but with a  short  pant length?
( How ( ( ( will that ) ( compare ( to ( ( the number ) ( who ( would ( ( buy ( the ( same product ) ) ) ( but ( with ( a ( short ( pant length ) ) ) ) ) ) ) ) ) ) ) ) ? ) )
(ROOT (SBARQ (WHADVP (WRB How)) (SQ (MD will) (NP (DT that)) (VP (VB compare) (PP (TO to) (NP (NP (DT the) (NN number)) (SBAR (WHNP (WP who)) (S (VP (MD would) (VP (VB buy) (NP (DT the) (JJ same) (NN product)) (PP (CC but) (PP (IN with) (NP (DT a) (JJ short) (NN pant) (NN length)))))))))))) (. ?)))
A product comparison with a small modification is essential to model development.
( ( ( A ( product comparison ) ) ( with ( a ( small modification ) ) ) ) ( ( is ( essential ( to ( model development ) ) ) ) . ) )
(ROOT (S (NP (NP (DT A) (NN product) (NN comparison)) (PP (IN with) (NP (DT a) (JJ small) (NN modification)))) (VP (VBZ is) (ADJP (JJ essential) (PP (TO to) (NP (NN model) (NN development))))) (. .)))