What will come in the place of the question mark $(?)$ in the following expression?
$43931.03 \div 2111.02 \times 401.04 = ?$

$\frac{1}{8}$ of $\frac{2}{3}$ of $\frac{3}{5}$ of $1715 = ?$

What is the value of $\frac{(0.5)^{3}-(0.1)^{3}}{(0.5)^{2}+0.5 \times 0.1+(0.1)^{2}}?$

Choose the incorrect relation$(s)$ from the following:
$(i)$ $\sqrt{6}+\sqrt{2}=\sqrt{5}+\sqrt{3}$
$(ii)$ $\sqrt{6}+\sqrt{2}<\sqrt{5}+\sqrt{3}$
$(iii)$ $\sqrt{6}+\sqrt{2}>\sqrt{5}+\sqrt{3}$

$\frac{\frac{1}{2} \div 4 + 20}{\frac{1}{2} \times 4 + 20} = ?$

Find the value of the following expression up to four places of decimals:
$\left[1+\frac{1}{1 \times 2}+\frac{1}{1 \times 2 \times 4}+\frac{1}{1 \times 2 \times 4 \times 8}+\frac{1}{1 \times 2 \times 4 \times 8 \times 16}\right]$