Help thanksss. its mutiple choice

What is the length of the segment joining the points at (4,5) and (6,-2) round to the nearest tenth if necessary

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?

Complete the equation of the line through (−10,3) and (−8,−8). use exact numbers.