When the test tube with sand was lowered into a beaker of water, the water level rose by 50 cm3

When the test tube with sand was lowered into a beaker of water, the water level rose by 50 cm3, while the test tube did not sink. What is the gravity on the tube?

If the test tube floats in water, then the force of gravity is balanced by the force of Archimedes, which is equal to the weight of the water displaced by the test tube:
P = F = ρ * g * V,
Where
ρ = 1000kg / m ^ 3 – water density,
g = 10m / s ^ 2 – acceleration of gravity,
V = 50cm ^ 3 = 5 * 10 ^ (- 5) m ^ 3;
From here
P = 0.5H;