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I know this is a stupid question- but when is the next leap year? A sphere has area 64 Im so confused in math. I am literally just stumped. I have no clue what I am doing? I've got a 700mm by 600mm tray. How many 25cm diameter tins will I be able to fit on it? How do I find "a" and the length of the other leg of the largest triangle without using proportions?