An electric dipole consists of two opposite charges of magnitude $q = 1 \times {10^{ - 6\;}}$ C separated by 2.0 cm. the dipole is placed in an external field of $1 \times {10^5}$ ${\rm{N}}{{\rm{C}}^{ - 1}}$. What maximum torque does the field exert on the dipole? How much work must an external agent do to turn the dipole end for end, starting from position of alignment (${\rm{\theta }} = {0^0}$)