A gas misture containing oxygen, nitrogen, and helium is trapped inside a vessel and exerts a total pressure of 925 torr. If the partial pressures of oxygen is 425 torr and helium is 75 torr, what is the partial pressure of nitrogen?
a. 400 atm
b. 415 atm
c. 400 torr
d. 425 torr
e. 435 torr