Someone please help this is due in 1hr

In the diagram of circle o, what is the measure of zabc?

The graph shows the decibel measure for sounds depending on how many times as intense they are as the threshold of sound. noise in a quiet room is 500 times as intense as the threshold of sound. what is the decibel measurement for the quiet room? 20 decibels28 decibels200 decibels280 decibels

:i need some real : a store sells shirts to the public at one pricing scale and wholesale at another pricing scale. the tables below describe the cost, y, of x shirts. (after tables) how do the slopes of the lines created by each table compare? the slope of the public table is 3/4 of the slope of the wholesale table.the slope of the wholesale table is 3/4 of the slope of the public table.the slope of the public table is 12 times greater than the slope of the wholesale table.the slope of the wholesale table is 12 times greater than the slope of the public table.