He baking soda looked like it dissolved in the vinegar. sarah and connor watched as the balloon expanded and filled with a gas. was this a physical or chemical reaction and why?

chemical - gas produced
k12 student here !

Hi. where is the graph?

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 .