commercially available cold packs are simple in design: a pouch with water on one side, isolated by a barrier from a specific salt on the other side. when the barrier is broken, the salt and water mix and the solution turns cold. select which of the statements is true about the reaction occurring in cold packs.

Which is a factor that might lead a person to make a career choice for the wrong reasons?

What is the least amount of money a student will receive when participating in work study ? a. $10 an hour b. federal maximum wage c. federal minimum wage d. $6 an hour

Raul has one solution that is 20% acid by volume and one solution that is 50% acid by volume. he plans to mix together some of each solution to create 30 milliliters of a solution that is 40% acid by volume. how many milliliters of the 20% acid solution should raul use to create the 40% acid solution? can someone explain this to me? i know that the answer is 10 milliliters, but i don't know how to get it.