Which of the following does not reduce Benedict's solution?

The cubic equation whose roots are the squares of the roots of $x^3-2x^2+10x-8=0$ is

An inductor of inductance $L=400\,mH$ and resistors of resistance $R_1=2\,\Omega$ and $R_2=2\,\Omega$ are connected to a battery of emf $E=12\,V$ as shown in the figure. The internal resistance of the battery is negligible. The switch $S$ is closed at $t=0$. The potential drop across $L$ as a function of time is

The maximum value of $x^4 e^{-x^2}$ is

The distance of the point $(1, 1, 9)$ from the point of intersection of the line $\frac{x-3}{1} = \frac{y-4}{2} = \frac{z-5}{2}$ and the plane $x+y+z=17$ is

Consider telecommunication through optical fibres. Which of the following statements is $NOT$ true?