If $a = i + j + k$,$b = i + j$,$c = i$ and $(a \times b) \times c = \lambda a + \mu b$,then $\lambda + \mu = $

The magnetic induction and the intensity of the magnetic field inside an iron core of an electromagnet are $1 \ Wb \ m^{-2}$ and $150 \ A \ m^{-1}$,respectively. The relative permeability of iron is $\left(\mu_0 = 4 \pi \times 10^{-7} \ H \ m^{-1}\right)$.

What is the role of limestone during the extraction of iron from haematite ore?

$A$ capacitor stores $60 \ \mu C$ charge when connected across a battery. When the gap between the plates is filled with a dielectric,an additional charge of $120 \ \mu C$ flows through the battery. The dielectric constant of the material inserted between the plates of the capacitor is

In the following indicator diagram,the net amount of work done will be

Which of the following groups of organisms can interbreed?