Complete and balance the following equations, and identify the oxidizing and reducing agents. (Recall that the O atoms in hydrogen peroxide, H2O2, have an atypical oxidation state.)

(a) NO2⁻¹(aq) + Cr2O7⁻²(aq) → Cr³⁺(aq) + NO3⁻¹(aq) [acidic solution]
(b) S(s) + HNO3(aq) → H2SO3(aq) + N2O(g) [acidic solution]
(c) H2O2(aq) + ClO2(aq) → ClO2⁻¹(aq) + O2(g) [basic solution]