Which of the following can be altered by the heat island effect?
A.
the ocean tides
B.
the movement of crustal plates
C.
local weather patterns
D.
local volcanic activity

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 .