Before you can register, you must answer 3 simple questions. All answers are numbers. If the answer is integer, simply type it in the corresponding field. A fraction must be typed in its simple irreducible form, i.e. 5/2 (neither 2.5, nor 2 1/2).

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A brick weighs 1 Kg and half a brick. How much does the brick weigh?

How many distinct natural divisors does the number 90 have?