11. (1.5) Calculate the average of the pH values at the first and second color changes. This is the pK,of bromocresol green.a. What must be true about the concentrations of HBG & HBG2 at this average pH that equals pK,?b. Given your response in part a, show that pH = pk, based on the dominant equilibrium and itssymbolic K expression.For the first pH value I got 3.82 and for the second, it is 7.80.