Buoyancy is the ability to float. If the weight of the object is greater than the weight of the water it displaces, it will sink. If the weight of the water it displaces is greater than the weight of the object, it will float. I made my boat hollow to make it weigh less. Stability is staying upright and withstanding pressure. I made the crescent moon shapes on both sides of my boat to hold coins and equally distribute the weight and to make it stable and sturdy.
Table of Buoyancy Calculations
My boat was kind of successful in meeting the design requirements. My boat was very buoyant compared with the other boats when tested by increasing the mass. My boat wasn't very stable compared with the others. It floated sideways and tipped over.
If I could reprint another 3D boat, I would wake it more stable and less buoyant because it was so buoyant that it compromised the stability. I would add pontoons to make it more stable. I would make the crescent moon shapes the same size. I would also make the keel shorter and I would make the hull wider because it was too tall.