If $$\overrightarrow{\mathrm A}\;=\;\mathrm{xy}\;{\widehat{\mathrm a}}_\mathrm x\;+\;\mathrm x^2\;{\widehat{\mathrm a}}_\mathrm y$$ then $$\oint\overrightarrow{\mathrm A}.\overrightarrow{\mathrm d}\mathcal l$$ over the path shown in the figure is

The value of the integral of the function $$\mathrm g\left(\mathrm x,\mathrm y\right)=4\mathrm x^3\;+\;10\mathrm y^4$$ along the straight line segment from the point (0, 0) to the point (1, 2) in the x-y plane is

If the electric field intensity is given by $$\mathrm E=\left(\mathrm x{\widehat{\mathrm u}}_\mathrm x\;+\mathrm y{\widehat{\mathrm u}}_\mathrm y+\mathrm z{\widehat{\mathrm u}}_\mathrm z\right)\;\mathrm{volt}/\mathrm m$$, the potential difference between X(2,0,0) and Y(1,2,3) is

A material has conductivity of 10^-2 mho/m and a relative permittivity of 4. The frequency at which the conduction current in the medium is equal to the displacement current is