Why does marullus ask, “where is thy leather apron and thy rule” in line 7

Marullus points out that if the Commoner is a carpenter, as he reports in line 6, he should not be out on the streets.

answer; /// the above statement is (true);

it is the background information on the characters and setting explained at the beginning of the story. the exposition will often have information about events that happened before the story began. the exposition is often the very first part of the plot.