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Damon makes 20 cups of lemonade by mixing lemon juice and water. the ratio of lemon juice to water is shown in the tape diagram. lemon juice\text{lemon juice} lemon juice water\text{water} water how much lemon juice did damon use in the lemonade? cups

Use the second shift theorem to find the inverse laplace transform of (e^−3s) / (s^2 + 2s − 3)

Which is the value of this expression when p=3 and q=-9