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Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of

Ron has 8 caps and 4 of his caps are blue. thes rest of his cap are red. how many of ron's caps are red

What line represents the relationship between r and s