Text: Note also that Equations (1) and (2) have the characteristic that eVb/eD = -eVws/eD for each observation point, including 1996.
Entailment: Equations and have the characteristic that eVb/eD = -eVws/eD for each observation point
Contradiction: Equations and have no characteristic that eVb/eD = -eVws/eD for each observation point