14) Air can be considered a mixture. Which statement helps describe air?
A)Air contains a fixed ratio of atoms.
B)The components of air separate into visible layers.
C)The components of air can be separated by chemical means.
D)The exact mixture of components varies from point to point.

Which of the following happens during cell division? (a) energy is created (b) waste is eliminated (c) carbon dioxide is released (d) damaged cells are replaced

What three natural resources are found in the great lakes region

Select the correct text in the passage. which sentences describe examples of sustainable living? i live in an old apartment building downtown, but my company is based in an office park on the outskirts of the city. i drive an old car that needs to be replaced. i plan to buy a hybrid for better gas mileage, but for now i am able to carpool with a couple of friends from work. the drive to the office park is about 45 minutes each way, but we do get to work in a modern building. the architects just received a leed certification for the design.