The dissolved oxygen present in any highly pressurized, hightemperature steam

The dissolved oxygen present in any highly pressurized, hightemperature steam boiler can be extremely corrosive to its metal parts. Hydrazine, which is completely miscible with water, can be added to remove oxygen by reacting with it to form nitrogen and water.
(a) Write the balanced equation for the reaction between gaseous hydrazine and oxygen.
(b) Calculate the enthalpy change accompanying this reaction.
(c) Oxygen in air dissolves in water to the extent of 9.1 ppm at 20°C at sea level. How many grams of hydrazine are required to react with all the oxygen in 3.0 × 104 L (the volume of a small swimming pool) under these conditions?