Help me plz tyy very much

How many solutions does the nonlinear system of equations graphed bellow have?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

The graph of the the function f(x) is given below. find [tex]\lim_{x \to 0\zero} f(x)[/tex] [tex]\lim_{x \to 1+\oneplus} f(x)[/tex] [tex]\lim_{x \to 0-\zeroneg} f(x)[/tex]