About $30 a person. They have a snack bar on board with bar
The price is depends on the package. I took the $30 package and did not get any food, but there is canteen who sells food and snacks.
Don't know about the cruise tour only, as I got the city pass. The pass costed me 80 bucks with 5 attractions in the city. The cruise tour is good and they have a snack bar as Dennis mentioned, but that's not free of cost.
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