Coal has the following analysis: carbon = 75%, hydrogen = 5%, oxygen = 6%, nitrogen = 1.5%, sulfur = 3%, water = 1.5%, and ash = 8%. Determine its heating value in Btu/lb. %3D

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After years of asking, you finally were allowed to go on a joy ride in your uncle’s 1956 Mercedes-Benz 300 SL. A notable feature of this vehicle is the gullwing door design that opens from a hinge at the top of the car. Unfortunately, you are having so much fun driving the car that you end up submerged in a fresh water lake. You sink to the bottom of the lake, which has a depth of 10 m. For the sake of simplicity, you can model the door as a 1 m × 1 m square plate, inclined at 45° relative to the floor of the lake. Neglect the weight of the door and friction in the hinge. How much force will be required to open the door, assuming you push from its geometric center?

Material Science