$A$ liquid does not wet the solid surface if the angle of contact is

Consider the general reaction given below at $400 \ K$: $xA_{(g)} \rightleftharpoons yB_{(g)}$. The values of $K_p$ and $K_c$ are studied under the same condition of temperature but variation in $x$ and $y$. $(i)$ $K_p = 85.87$ and $K_c = 2.586$ (appropriate units). $(ii)$ $K_p = 0.862$ and $K_c = 28.62$ (appropriate units). The values of $x$ and $y$ in $(i)$ and $(ii)$ respectively are:

Let $f(x) = x^3 + bx^2 + cx + d$ where $0 < b^2 < c$. Then $f(x)$:

Four convergent lenses have focal lengths $100 \, cm, 10 \, cm, 4 \, cm$ and $0.3 \, cm$. For a telescope with maximum possible magnification,we choose the lenses of focal lengths:

If the difference between the roots of the equations $x^2+ax+b=0$ and $x^2+bx+a=0$ is the same,and $a \neq b$,then:

$A$ plane passing through $(-1, 2, 3)$ and whose normal makes equal angles with the coordinate axes is