Which statement represents the biconditional statement of the conditional statements? if the measures of two angles have a sum of 90º, then the angles are complements. if two angles are complements, then their measures have a sum of 90º. a. the measures of two angles have a sum of 90º if and only if the angles are not complements. b. the measures of two angles do not have a sum of 90º if and only if the angles are complements. c. the measures of two angles have a sum of 90º if and only if the angles are complements. d. the measures of two angles do not have a sum of 90º if and only if the angles are not complements.