A 0.419 g of sample of H₂O (m_M = 18.015 g mol^-1) is added to a 2.30 L flask containing some Kr (m_M = 83.80 g mol^-1) gas. The flask is heated to 296.28 °C at which temperature all of the water is converted to the gaseous phase, giving a total pressure in the flask of 3.503 atm.

(a)  Calculate the partial pressure of H₂O (in atm) in the flask at 296.28 °C.
(b) Calculate the partial pressure of Kr (in atm) in the flask at 296.28 °C.

(c)  Calculate the mole fraction, X, of Kr in the flask at 296.28 °C.