f0 = 140 cm, fe = 5 cm.
(a) When the final image is formed at infinty.
m = -f0/fe = 140/-5 = -28
(b) When the final image isformed at the least distance of distinct vision.
m = f0/fe(1 + fe/d) = 140/5(1 + 5/25)
= 140/5((25 + 5)/25) = 140/5 x 30/25 = 33.6