Which of the above optical system is lens?
I, V, IV, II
I, II, III, V
I, II, III, IV
I, IV only
The fifth optical system has two plane mirrors hence it can't be considered as lens. Lens should have at least one spherical mirror.
Digital signals
(i) Do not provide a continuous set of values,
(ii) Represent values as discrete steps,
(iii) Can utilize binary system, and
(iv) Can utilize decimal as well as binary systems.
Which of the above statements are true?
(a) (i) and (ii) only
(b) (ii) and (iii) only
(c) (i), (ii) and (iii) but not (iv)
(d) All of (i), (ii), (iii) and (iv).