The henrys law constant for the solubility of N2 gas in water at 298k is 1.0×105 atm. The mole fraction of N2 in air is 0.8 . The number of moles of N2 from air dissolved in 10moles of water of 298k and 5atm pressure is
a)4.0×10-4
b)4.0×10-5
C) 5×10_5
d) 4×10_6