The dimension of $${1 \over 2}{\varepsilon _0}{E^2}$$, where $${\varepsilon _0}$$ is permittivity of free space and E is electric field, is

If the dimensions of a physical quantity are given by M^aL^bT^c, then the physical quantity will be

If the error in the measurement of radius of a sphere is 2%, then the error in the determination of volume of the sphere will be

Which two of the following five physical parameters have the same dimensions ?
1.  Energy density
2.  Refractive index
3.  Dielectric constant
4.  Young's modulus
5.  Magnetic field