What is the concentration of the base (koh) in the following titration, given the data below?
0.75 m hbr unknown koh
initial burette reading
0.0 ml
0.5 ml
final burette reading
22.6 ml
37.5 ml

To calculate the concentration of the base based on the titration, the concept used is the equal of number of equivalence of the acid used to that of the base. From this,
                                 Na x Va = Nb x Vb
For HBr and KOH, molarity is equal to normality. Substituting the known values,
          (0.75 M) x (22.6 mL - 0 mL) = Nb x (37.5 mL - 0.5 mL) 
                                         Nb = 0.46 N
                                          Mb = 0.46 M
Thus, the concentration of the base is approximately 0.46 M. 

What do you mean by that? like the contents? the thc level?

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 .