Math question is attached below

In a school 2/3 of the students study a language of those who study a language 2/5 study french

Write an algebraic expression to match each statement a. four less than 8 times a number b. twice the difference of a number and six c. nine from a number squared

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.