I need help with this practice problem solving It asks to answer by in filling in the four boxes

The polar form of a complex number a + ib is given by:
[tex]r\cdot cis(\theta)[/tex][tex]\begin{gathered} \text{ Where} \\ r=\sqrt{a^2+b^2} \\ \theta=\arctan(\frac{b}{a}) \end{gathered}[/tex]In this case,
[tex]\begin{gathered} a=2\sqrt{3} \\ b=-2 \end{gathered}[/tex]Therefore,
[tex]r=\sqrt{(2\sqrt{3})^2+(-2)^2}=\sqrt{12+4}=\sqrt{16}=4[/tex]and
[tex]\begin{gathered} \theta=\arctan(-\frac{2}{2\sqrt{3}})=\arctan(-\frac{1}{\sqrt{3}})=330^{\circ} \\ in\text{ radians} \\ \theta=\frac{11\pi}{6}\text{ radians} \end{gathered}[/tex]The root is given by:
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