1. The problem statement, all variables and given/known data We are in a planet where the gravitational acceleration is 1 ms-2. Tankers fly over the surface of a liquid ammonia lake (at 239K) at a height of 40m. A special, insulated, frictionless tube is lowered into the ammonia 1m below the surface. We want to draw up ammonia through the tube into an insulated tank by the forward motion of the tanker without pumping. The tank is initially full of hydrogen at 5 bar and 239K. The hydrogen is displaced through a vent at the top of the tanker by the incoming ammonia. The maximum depth of ammonia in the tank is 10m (the bottom of the tank forms the base). What is the minimum speed the tanker must fly over the lake to fill its tank? 2. Relevant equations 1/2 mv^2=mgh???? F=ma??? 3. The attempt at a solution the total height the ammonia has to travel to reach the tank is 41m. Something to do with the height and gravitational acceleration? And the maximum height of ammonia? And the pressure of the hydrogen in the tank initially????