Which of the following is a bad conductor of electricity?

From the origin,chords are drawn to the circle $(x - 1)^2 + y^2 = 1$. The equation of the locus of the midpoints of these chords is:

The angle between the curves $y^2=4x+4$ and $y^2=36(9-x)$ is (in $^{\circ}$)

$C_6H_6 + 3O_3$ $\longrightarrow X \stackrel{Zn / H_2O}{}$ ${\longrightarrow} Y$; $X$ and $Y$ are respectively

Given the standard electrode potentials,
$K^{+} / K = -2.93 \ V$,$Ag^{+} / Ag = 0.80 \ V$
$Hg^{2+} / Hg = 0.79 \ V$
$Mg^{2+} / Mg = -2.37 \ V$,$Cr^{3+} / Cr = -0.74 \ V$
Arrange these metals in their increasing order of reducing power.

In which of the following reactions is hydrogen gas not liberated?