Please help me please do them all its just thrree

How much dextrose 70% must be mixed with dextrose 5% to prepare 1,000 ml of dextrose 20%?

In stepmber, daniel and justin opened a business. during their first three months of business, their average monthly profit was $51. if during their first month, they lost $29, and during their second month, they gained $115, what was their profit or loss for their third plzzz i will give you 299 points

The volume of a rectangular prism is found by multiplying the length, width, and height of the prism. a rectangular prism has a width of 5x^2units, a length of 7x^3 units and a height of 2x^4 units. which is the volume of the prism in terms of x?