A lava flow is threatening to engulf a small town. A 400-m wide, 35-cm-thick tongue of 1200°C lava is advancing at the rate of 1.0 m per minute. The mayor devises a plan to stop the lava in its tracks by flying in large quantities of 20°C water and dousing it. The lava has density 2500 kg/m³, specific heat 1100 J/kg K, melting temperature 800°C, and heat of fusion 4.0 × 10⁵ J/kg. How many liters of water per minute, at a minimum, will be needed to save the town?