If the lines $4x + 3y - 1 = 0$,$x - y + 5 = 0$,and $kx + 5y - 3 = 0$ are concurrent,then $k$ is equal to:

The incentre of the triangle with vertices $(1, \sqrt{3})$,$(0, 0)$ and $(2, 0)$ is

Into how many kingdoms is the domain $Eukarya$ divided?

Which of the following methods is generally used for the extraction of alkali metals?

$1.5 \ g$ of $CdCl_2$ was found to contain $0.9 \ g$ of $Cd$. Calculate the atomic weight of $Cd$.

$A$ uniform metal rod is used as a bar pendulum. If the room temperature rises by $10^{\circ} C$ and the coefficient of linear expansion of the metal of the rod is $2 \times 10^{-6} /^{\circ} C$,the period of the pendulum will have a percentage increase of