What specific value from the graph is needed, in addition to the information in part (c) above, to calculate the molar concentration of the NaOH(aq) ?

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

i'm assuming that the correct answer is indeed the first one/ "a"..

wher is the rest of the question

12 is it do you think so