In the following chemical reactions, identify the acid, conjugate acid, base, and conjugate base.
a)nh3(aq) + h2o(l) = nh4+(aq) + oh-(aq)
b)h2o(l) + h2o(l) = h3o+(aq) + oh-(aq)
c)h2co3(aq) + oh-(aq) = hco3-(aq) + h2o(l)
d)h2co3(aq) + h2o(l) = hco3-(aq) + h3o+(aq)