Although Amulek has agreed to answer questions, Zeezrom does not ask a single question. Instead, he offers a bribe, which implicitly questions how serious Amulek is about his message. Had Amulek accepted the money, there would be no need for other questions.
Mormon explained the various measures so that his readers would understand the value of the offered onti. An onti was the largest measure of silver (v. 13). The measures increased in terms of two or four. Six onties might be analyzed as a “full set” of four and half of another. Regardless of the actual purchasing power, the mathematical exaggeration of the number (half again more than a “full set”) sends an emotional message of a significant sum.