Most air pollution is caused by
solid waste disposal
burning nonrenewable resources
geothermal energy
habitat destruction

How does a bone marrow transplant treat sickle cell disease?

How many calories are in one pound of fat

*edit* i took the test and i picked a and it was incorrect for its c! rank the following suggestions for preventing std, in order of increasing effectiveness. 1) using latex condoms properly 2) using spermicidal foam or jelly with a monogamous partner 3) abstaining from sexual intercourse and genital contact a. 1, 2, 3c. 2, 1, 3