there are way too ,any variables to answer your question. It depends on the boat, the boat size, weight, kind of prop and pitch etc.
Type your answer here... Mainly engine size, overall weight, hull design.
Depends on the size of the engine in the boat.
Not enough info. There are too many other variables. Speed of a boat is dependent on boat length, whether it is a planning hull, what size and pitch propeller does it have, and weight of the boat. So it is impossible to answer this based only on the size of the engine.
Ok well by "size" do you mean a persons size? a boat size or what? In racing peoples body weight is a very significant factor with Olympic sailors shedding as much weight as possible before an event. For instance - A top racing crew weight in a 420 class dinghy should weigh about 120kg to 130kg. Also a boats length has an effect on the speed of the boat. If you put a 50hp engine on a little tender then itsll go X speed. If you replace it with a 100hp engine it will still go X speed. This has something to do with the "waterline length" of the boat.
you usually judge boat speed depending on its size. if its a smaller boat then it would be by MPH. but for bigger boats they go by knots
depends on the size. a trailer boat=30mph a ski boat=60mph
size of the engine
The 2013 Bentley Continental-GT-Speed has a 6.0 L base engine size.
The 2014 Bentley Continental-GT-Speed has a 6.0 L base engine size.
The 2009 Bentley Continental-GT-Speed has a 6.0 L base engine size.
The 2010 Bentley Continental-GT-Speed has a 6.0 L base engine size.