A mixture of three gases has a total pressure of 950 torr. The second gas exerts 370 torr, the third exerts 58 kPa. What pressure does the first gas gas exert? 230 torr
1465 torr
145 torr
522 torr
805 torr
435 torr

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

the answer is 0.42 is that is an option. this question provides no info