An alloy of tin is 18% tin and weighs 30 pounds. how many pounds of tin are in the alloy?

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Apatient is to be given 35 milligrams of demerol every 4 hours. you have demerol 50 milligrams/milliliter in stock. how many milliliters should be given per dose?

I’m still confused on how to work the percentages