SUPPOSE TWO SETS A ={a, b} and B={1,2,3,x, y} find A. B

Quick translate "x is 12 units from 20" into an equation. what are the values of x being described? if you can answer any of my other questions that'd be great too

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?