Explain why a test tube immersed at a certain angle in a tumbler of water appears to have a mirror sluface for a certain viewing position? `(AS_(7))`

A man is standing against a wall such that his right shoulder and right leg are in contact with the surface of the wall along his height. Can he raise his left leg at this position without moving his body away from the wall? Why? Explain. (AS_(7))

In a certain region of space, electric field is along the z-direction throughout. The magnitude of electric field is, however, not constant but increases uniformly along the positive z-direction, at the rate of 10^5 NC^(-1) per meter. What are the force and torque experienced by a system having a total dipole moment equal to 10^(-7) cm in the negative z-direction ?