This is my attempt to explain air pressure in ductwork. This video is part of the heating and cooling series of training videos made to accompany my websites... This is my attempt to explain air pressure in ductwork. This video is part of the heating and cooling series of training videos made to accompany my websites... Skip navigation
Medical marijuana refers to the use of the Cannabis plant as a physician-recommended herbal therapy as well as synthetic THC and cannabinoids. So far, the medical use of cannabis is legal only in a limited number of territories, including Canada, Belgium, Australia, the Netherlands, Spain, and several U.S. states.
What is marijuana? Marijuana (grass, pot, weed) is the common name for a crude drug made from the plant Cannabis sativa. The main mind-altering (psychoactive) ingredient in marijuana is THC (delta-9-tetrahydrocannabinol), but more than 400 other chemicals also are in the plant. A marijuana joint (cigarette) is made from the dried particles of the plant.