What mole fraction of O2 is necessary for the partial pressure of O2 to be 2.80 atm when the total pressure is 4.59 atm?

You can still be friends with each other. you don't have to date since he likes someone else. just stick to being friends for now

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .