The rectangular boat shown below has base dimensions 10.0 cm × 8.0 cm. each cube has a mass of 40 g, and the liquid in the tank has a density of 1.0 g/ml. how far has the boat sunk into the water?

When boat is sunk into the liquid the net buoyancy on the boat is counterbalanced by weight of the boat

So here weight of the boat = Buoyancy force

let say boat is sunk by distance "h"

now we can say

now by above force balance equation we can write

so boat will sunk by total 5 mm distance

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.

scientific laws are the result of testing theories and proving them to be facts.