Which of the following is a non-reducing sugar?

Solution $X$ contains $Na_2CO_3$ and $NaHCO_3$. $20 \ mL$ of $X$ when titrated using methyl orange indicator consumed $60 \ mL$ of $0.1 \ M$ $HCl$ solution. In another experiment,$20 \ mL$ of $X$ solution when titrated using phenolphthalein consumed $20 \ mL$ of $0.1 \ M$ $HCl$ solution. The concentrations (in $mol \ L^{-1}$) of $Na_2CO_3$ and $NaHCO_3$ in $X$ are respectively:

The incorrect statement regarding the following reactions is:
$XeF_6 + \text{Excess } H_2O \rightarrow 'X' + HF$
$XeF_6 + 2 H_2O \rightarrow 'Y' + HF$

Which substance is used as a gaseous insulator in high-voltage generators?

The periodic time of a particle doing simple harmonic motion is $4 \ s$. The time taken by it to go from its mean position to half the maximum displacement (amplitude) is

$A$ uniform cylinder of length $L$ and mass $M$ having cross-sectional area $A$ is suspended,with its length vertical,from a fixed point by a massless spring such that it is half submerged in a liquid of density $\sigma$ at equilibrium position. The extension $x_0$ of the spring when it is in equilibrium is: