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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?

Which system of linear inequalities is represented by the graph? x-3y > 6 and y? 2x + 4 x + 3y > 6 and y? 2x - 4 x - 3y > 6 and y? 2 - 4 x + 3y > 6 and y > 2x + 4 no be 2 -1.1 1 2 3 4 5 submit save and exit next mark this and retum be

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).