Select all the expressions that represent a 20% discount off the price of an item that originally costs d dollars.

How many liters of 60% alcohol solution should be added to 40 liters of a 20% alcohol solution to make a 50% solution?

These three organisms are interdependent on each other for their survival. what will happen if foxes are eliminated from the region? a. there will be more rabbits and less grass in the region. b. there will be more grass and fewer rabbits in the region. c. there will be fewer rabbits and less grass in the region. d. there will be more rabbits and more grass in the region.

It takes longer to fly an airplane against a with it