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I need to describe two ways I would measure moles in chemistry lab and identify any equipment I would use? Could a black hole exist within the event horizon of a bigger black hole? Help me to solve the following question!
Find integers x and y such that 57x+79y=17, and 400 ~ x + y + z = 3, x² + y² + z² = 5, x³ + y³ + z³ = 7 ➪ x⁴ + y⁴ + z⁴ = ? In equal-tempered tuning the frequency (in Hz) of the note one tone above 220 Hz is...?