A certain weak base has a Kᵣ of 7.20 x 10⁻⁷M. What concentration of this base will produce a pH of 10.16?
a) 1.0 x 10⁻⁷ M
b) 7.20 x 10⁻⁷ M
c) 1.0 x 10⁻⁹ M
d) 7.20 x 10⁻⁹ M