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In simplified exponential notation, the expression a^2•a^-3•a 1/a 0

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

The weight of an object in the water is 7% of its weight out of the water. what is the weight of a 652g object in the water?