Fill in the blank to make the following statement true:
The square root of $121$ is ..........

Simplify: $64^{-\frac{1}{3}} + 64^{\frac{1}{3}} - 64^{\frac{2}{3}}$

Simplify: $\frac{7 \sqrt{3}}{\sqrt{10}+\sqrt{3}}-\frac{2 \sqrt{5}}{\sqrt{6}+\sqrt{5}}-\frac{3 \sqrt{2}}{\sqrt{15}+3 \sqrt{2}}$

Visualise $-4.126$ on the number line,using successive magnification.

Find the value of the following expression correct to three decimal places,rationalizing the denominator if needed. Given $\sqrt{2} = 1.414$,$\sqrt{3} = 1.732$,and $\sqrt{5} = 2.236$.
$\frac{1}{\sqrt{3} + \sqrt{2}}$

For each question,select the proper option from four options given,to make the statement true: $4 . \overline{185} = \ldots \ldots$