A metallic barrel has a capacity of 280.0 l at a temperature of 10°C. The barrel is filled with an oil mixture up to the 150 l mark and sealed. What is the pressure inside the container if the temperature is increased to 80°C? Consider that atmospheric pressure is 1.01 × 10⁵ Pa and the coefficients of volume thermal expansion are βoil = 270× 10⁻⁶ K⁻¹ and βbarrel = 20 × 10⁻⁷ K⁻¹.