The density of the blade is constant throughout its length, and so a 10%-mass. fragment will have a cross-sectional area of 10% of the full blade. In practice, the. area of a 10%-mass fragment will vary depending upon its shape, and upon whether. it consists of the only the outer shell or the internal beams as well.
Marijuana use ranks second behind alcohol in regards to the most commonly abused drugs by teenagers. There has been an increase in marijuana use among teenagers due to the increasing societal attitudes towards tolerance and perceptions that marijuana is not a dangerous drug.
(Baby Boomers) In 2007, the rate of past year use in this age group [persons aged 50 to 59] was 9.4 percent for any illicit drug, 5.7 percent for marijuana, and 4.0 percent for nonmedical use of prescription drugs.Estimated Prevalence of Marijuana Use in the US, 2013).  Marijuana was the most commonly used illicit drug in 2013. There were 19.8 million past month users in 2013 (7.5 percent of those aged 12 or older), which was similar to the number and rate in 2012 (18.9 million or 7.3 percent).