Imp Operation Details

1. What is the "cube rule" in international maritime transport? How does it work and what are important limitations?
2. An owner accepted a freight rate of US$ 10/t for a parcel of 100,000t. The round voyage back to where the owner started is 8,000 nm. The ship has a design-consumption of 45 tons per day at a speed of 14 knots. A ton of bunker fuel currently costs US$ 400 per ton. The owner expects to receive the same freight rate for the same cargo size, once the ship has completed the voyage. Compute if the ship should travel at 14, 12 or 10 knots in order to maximise the profit. Ignore sea-margins or cargo handling times.