For a first order reaction, (A) → products, the concentration of A changes from 0.1M to 0.025M in 40minutes. The rate of reaction when the concentration of A is 0.01M is
(a) 3.47 × 10–4M/min
(b) 3.47 × 10–5M/min
(c) 1.73 × 10–4M/min
(d) 1.73 × 10–5M/min
