Find Value ofCOS2A-Cos2B - cos2C​

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?

The measure of an angle is 117°. what is the measure of a supplementary angle?

Heather is riding a quadratic function that represents a parabola that touches but does not cross the x-axis at x=-6