Answer A
Explanation: it gave more power to common people
A shaduf is a large pole balanced on a crossbeam, a rope and bucket on one end and a heavy counter weight at the other. By pulling the rope it lowered the bucket into the canal. The farmer then raised the bucket of water by pulling down on the weight. He then swung the pole around and emptied the bucket onto the field.
The ship's watertight bulkheads could have been extended and fully sealed to reduce the risk of flooding. Titanic was constructed with transverse bulkheads (i.e. walls) to divide the ship into 16 watertight compartments, which could be sealed off with doors operated either manually or remotely from the bridge.
