State the rule to determine the direction of a     (3 marks)

(i) magnetic field produced around a straight conductor-carrying current,

(ii) force experienced by a current-carrying straight conductor placed in a magnetic field which is perpendicular to it, and

(iii) current induced in a coil due to its rotation in a magnetic field.

(iv) Current induced in a circuit by the changing magnetic flux due to the motion of a magnet.