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Which is the official bitcoin website where i get the the mathematical puzzles to solve? Find the frequency of the following wavelength;
1.8×10^-5 m? How much solar energy (in watts per square meter) reaches Pluto's surface? Grams to mole conversions: 60.0 grams of potassium sulfate ,
Thanks? What are the last two non-zero digits of 2017! (factorial)?