An acid-catalysed ester hydrolysis is followed by titration. The titres are 10.0 mL at t = 0, 20.0 mL at t = 20 min and 30.0 mL at infinite time. Assuming first-order kinetics ($\ln 2=0.693$), which statements are correct?

1. AThe rate constant is 0.0693 $\mathrm{mi}{\mathrm{n}}^{-1}$
2. BThe half-life is 20 min
3. CThe titre at t = 60 min is 27.50 mL
4. DThe titre at t = 40 min is 25.00 mL