(A) anode voltage drops from 10 % of its initial value to zero (X)
(B) anode current rises from 90 % to its final value ()
(C) both (A) and (B) (X)
(D) anode current rises from 10 % to 90 % of its final value (X)
Answers: Spread time is defined as the interval during which anode current rises from 90 % to its final value.