How does the nucleus of a copper atom compared to the nucleus of a nickel atom

Copper has 29 protons in the nucleus, while Nickel has 28 protons.

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 .