PLEASE HELP ASAP Which of the following is an example of work.
O A pencil laying on top of a desk.
O A dog wagging its tail.
O A box sitting on the floor.
O A car that is parked.

ITS B
A dog wagging its tail

A dog wagging its tail

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 .