The expected answers were:
(a)        The liberation of electrons from an element other than the cathode of a valve by high velocity electrons
(b)        (i)         Focus anode
             (ii)        Accelerating anode
             (iii)       Final anode
             (iv)       First anode
             (v)        Second anode
(c)        gm = transconductance
             amplification factor
             ra  =  anode resistance
(d)

The question was on Electron Emission. The question was attempted by many candidates. Many confused the parameters transconductance/mutual conductance , plate resistance, amplification factor with the device’s electrodes which incidentally was a repeat of past question. The performance was average.