The figure shows Tap S, Tap T and an empty tank with a capacity of 89.2 litres. Water flows Tap S at 1.5 litres per minute and from Tap T at 1.1 litres per minute. Tap S was turned on first. Tap T was turned on 4 minutes later. The taps were turned off at the same time when the tank was completely filled without overflowing. How much water flowed from Tap S?