The colour of light absorbed by an aqueous solution of $CuSO_4$ is

Which of the following cannot give iodometric titrations?

This is the only type of pollination which during pollination brings genetically different types of pollen grains to the stigma.

The thickness of a uniform rectangular metal plate is $5 ~mm$ and the area of each surface is $5 ~cm^2$. In steady state, the temperature difference between the two surfaces of the plate is $14^{\circ} C$. If the heat flowing through the plate in one second from one surface to the other surface is $42 ~J$, then the thermal conductivity of the metal is:

The half-life of $Ra^{226}$ is $1620$ years. Calculate the number of atoms that decay in one second in $1 \ g$ of radium (Avogadro number $= 6.023 \times 10^{23}$).

The function $f(x) = |x| + \frac{|x|}{x}$ is