A thin walled cylindrical metal vessel α=10−3K−1 contains a liquid γr=10−3K−1. If the vessel and its contents are now heated by 10 K the pressure due to the liquid at the bottom

The density of liquid at the elevated temperature ' ρ=ρ01+3α-γr△t. Now hydrostatic pressure p=ρgh and since ρ decreases ,p also decreases. Percentage change in pressure =p0-pp0×100%=2%,