If $-1+\sqrt{3}i=r{e}^{i\theta }$ then $\theta =$.

Simplify the following and express in the form $a+ib$

$3+\sqrt{-64}$

Simplify the following and express in the form $a+ib$

${\left(2i^3\right)}^2$

Simplify the following and express in the form $a+ib$

$(2+3i)(1-4i)$

Simplify the following and express in the form $a+ib$

$\frac{5}{2}i(-4-3i)$

Simplify the following and express in the form $a+ib$

$(1+3i{)}^2(3+i)$

Simplify the following and express in the form $a+ib$

$\frac{4+3i}{1-i}$

Simplify the following and express in the form $a+ib$.

$\left(1+\frac{2}{i}\right)\left(3+\frac{4}{i}\right)(5+i{)}^{-1}$