$\frac{(469+174)^{2}-(469-174)^{2}}{469 \times 174} = ?$

The value of $\frac{(0.96)^{3}-(0.1)^{3}}{(0.96)^{2}+0.096+(0.1)^{2}}$ is

If $x = 1 + \sqrt{2} + \sqrt{3},$ then find the value of $x^{2} - 2x + 4$.

If $x+\frac{1}{x}=2,$ then the value of $x^{100}+\frac{1}{x^{100}}$ is

In an examination,a student scores $4$ marks for every correct answer and loses $1$ mark for every wrong answer. If he attempts in all $60$ questions and secures $130$ marks,the number of questions he attempts correctly is

If $\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right) \ldots\left(1-\frac{1}{70}\right)=\frac{x}{70},$ then what is the value of $x ?$