Which statement is correct? A. Atomic radius decreases down group 17.
B. First ionization energy decreases down group 1.
C. Atomic radius increases across period 3 from Na to Cl.
D. First ionization energy decreases across period 3 from Na to Cl.

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 .

Sorry i dont understand the question can you rephase it?

C. definite shape, definite volume. that is a solid.