Question : What is the value of $\left[\frac{1}{5}+\left\{\frac{1}{6}\right.\right.$ of $\left.\left.\left(\frac{42}{35} \div \frac{6}{25}\right)–\left(\frac{2}{7} \times \frac{6}{5} \div \frac{18}{42}\right)\right\}+\frac{19}{30}\right]$?

Question : The value of $\left[\frac{1}{4}\right.$ of $\left.18 \div \frac{6}{5} \text{of}\left(\frac{1}{8}+\frac{7}{4}\right)\right] \times \frac{1}{15}$ is:

Question : What is the value of $\frac{\left(\frac{28}{9} \times \frac{42}{35}\right) \div\left(\frac{3}{25} \times \frac{5}{7} \div \frac{1}{21}\right)}{\left(\frac{14}{15} \div \frac{2}{75} \text { of } \frac{7}{5}\right) \times \frac{1}{75} \div \frac{4}{3}} ?$

Question : Find the value of $\sqrt{\left[\left(13^2-8^2\right) \times 5+4\right]}$ :

Question : $2+\frac{6}{\sqrt{3}}+\frac{1}{2+\sqrt{3}}+\frac{1}{\sqrt{3}-2}$ equals to: