Air Pressure at the Bottom of Death Valley,at 282 Ft

Air pressure at the bottom of Death Valley,at 282 ft below sea level,is 776 mm Hg. What are the partial pressures of O₂ and N₂,which compose 21% and 78% of the atmosphere,respectively?

A) 210 mm Hg O₂ and 780 mm Hg N₂
B) 160 mm Hg O₂ and 610 mm Hg N₂
C) 160 mm Hg O₂ and 590 mm Hg N₂
D) 163 mm Hg O₂ and 613 mm Hg N₂