Oxygen and cyclopropane at partial pressures orf 570 torr and 170 torr respectively are mixed in a gas cylinder. What is the ratio of the number of moles of cyclopropane to the number of moles of oxygen?
A. `(170)/(740)=0.23`
B. `((170)/(742))/([(170)/(42)+(570)/(32)])=0.19`
C. `(170+42)/(570+32)=0.39`
D. `(170)/(570)=0.30`
