Can someone explain this to me? what i need to do?

Average salary for a medical assistant is $31,220 which is a 20% income tax bracket how much money would they pay in income tax?

Figure abcd is a parallelogram. if point c lies on the line x = 2, what is the y-value of point c?

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]