Science Which of the following is not part of the cell theory?
A. All cells come from pre-existing cells
B. All cells contain the same organelles within them
C. Cells are the basic unit that can sustain life
D. All living things are made up of one or more cells.
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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 .