Compression of a filled test chamber

A rigid test assembly initially contains $0.300\,\mathrm{m^3}$ of a liquid. During a slow pressure test the liquid pressure rises by $4.0\,\mathrm{MPa}$; its bulk modulus may be treated as constant at $2.1\,\mathrm{GPa}$. Estimate the fractional reduction in liquid volume, express it as a percentage, and calculate the magnitude of the volume reduction. The assembly has a compensating piston allowing this small reduction.