If 0.40 L of a gas are under a pressure of 800.0 torr, what would the volume of the gas be at a pressure of 1000.0 torr?
A. 3.2 L
B. 0.32 L
C. 320 mL
D. 32 mL

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 .

The answer is 4 i don't know if its right let me see.