Oscillations Part 2

A light hollow cube of side length 10 cm and mass 10 g , is floating in water. It is pushed down and released to execute simple harmonic oscillations. The time period of oscillations is yπ×10−2 s, where the value of y is
(Acceleration due to gravity, g=10m∕ s2, density of water =103‌kg∕m3 )