Please help on question 10!!! I will give you lots of points for it!

You work for a lender that requires a 20% down payment and uses the standard depth to income ratio to determine a person‘s a little eligibility for a home loan of the following choose the person that you would rate the highest on their eligibility for a home loan

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?

Does the point (1, sqrt 7) lie on circle shown.