This is a function whose degree of x is 2.

These are functions symmetric on the origin.

This is a function whose form is $f(x)=|x|$

This is a function whose graph is a parabola. 

This is an example of a periodic function. 

This is a function whose form is $f(x)=\frac{g\left(x\right)}{h\left(x\right)}$ .

This is a function whose form is  $f(x)=\sqrt[n]{x}$

These are functions wherein its graph repeats itself over cycles for x in the domain of the function. 

This is a function whose degree of x is 3.

This is a function whose graph is a line.