Simplify the following:
$\sqrt{45}-3 \sqrt{20}+4 \sqrt{5}$

Express $0.\overline{83}$ in the form $\frac{p}{q}$, where $p$ and $q$ are integers and $q \neq 0$.

Express $0.6 + 0.\overline{7} + 0.4\overline{7}$ in the form $\frac{p}{q},$ where $p$ and $q$ are integers and $q \neq 0$.

State whether the following statement is true or false:
$\sqrt{49}$ is an irrational number.

For each question,select the proper option from four options given,to make the statement true: $\sqrt{5^{2}+12^{2}}$ is a / an $\ldots \ldots$ number.

Which of the following is equal to $x$?