Hello can someone answer lol my little sister wants me to turn my tablet off

Need ! give step by step solutions on how to solve number one [tex]\frac{9-2\sqrt{3} }{12+\sqrt{3} }[/tex] number two [tex]x+4=\sqrt{13x-20}[/tex] number three (domain and range) [tex]f(x)=2\sqrt[3]{x} +1[/tex]

Find the domain and range of the following function f(x) = 51x - 21+ 4

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