At the shopping mall, Joaquin bought 4 pretzels and 2 bottles of water for $13.00. Kelly bought 3 pretzels and a bottle of water for $9.00. What is the price of a bottle of water? A bag of pretzels?

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There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?

What is the simplified form of square root of 400 to the 100th power ?