What Is the [H₃O⁺] in a Solution That Consists of 1.5

Multiple Choice

What is the [H₃O⁺] in a solution that consists of 1.5 M NH₃ and 2.5 NH₄Cl? K_b = 1.8 * 10¯⁵

A) 1.1 * 10¯⁵ M
B) 3.0 * 10¯⁶ M
C) 3.3 * 10¯⁹ M
D) 9.3 * 10¯¹⁰ M
E) None of these choices is correct.