A consultant advises the owners of a phone company that their profit p each month can be modeled by
p(x) = -50x2 + 3500x - 2500
The variable x is the average cost that a customer is charged. What
range of costs will bring in a profit of at least $40,000?

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