4) Not enough is known about how nontransportation costs vary with distance.
( ( 4 -RRB- ) ( ( Not enough ) ( ( is ( known ( about ( how ( ( nontransportation costs ) ( vary ( with distance ) ) ) ) ) ) ) . ) ) )
(ROOT (S (LST (LS 4) (-RRB- -RRB-)) (NP (RB Not) (JJ enough)) (VP (VBZ is) (VP (VBN known) (PP (IN about) (SBAR (WHADVP (WRB how)) (S (NP (NN nontransportation) (NNS costs)) (VP (VBP vary) (PP (IN with) (NP (NN distance))))))))) (. .)))
The ways in which distance affects nontransportation costs is a subject we don't have enough information on.
( ( ( The ways ) ( ( in which ) ( distance ( affects ( nontransportation costs ) ) ) ) ) ( ( is ( ( a subject ) ( we ( ( do n't ) ( ( have ( enough information ) ) on ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NNS ways)) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (NN distance)) (VP (VBZ affects) (NP (NN nontransportation) (NNS costs)))))) (VP (VBZ is) (NP (NP (DT a) (NN subject)) (SBAR (S (NP (PRP we)) (VP (VBP do) (RB n't) (VP (VB have) (NP (JJ enough) (NN information)) (PP (IN on)))))))) (. .)))