The British high-definition TV service started trials in August 1936 and a regular service on 2 November 1936 using both the (mechanical) Baird 240 line sequential scan (later to be inaccurately rechristened 'progressive') and the (electronic) Marconi-EMI 405 line interlaced systems. The Baird system was discontinued in February 1937. In 1938 France followed with their own 441-line system, variants of which were also used by a number of other countries. The US NTSC 525-line system joined in 1941. In 1949 France introduced an even higher-resolution standard at 819 lines, a system that should have been high definition even by today's standards, but was monochrome only and the technical limitations of the time prevented it from achieving the definition of which it should have been capable. All of these systems used interlacing and a 4:3 aspect ratio except the 240-line system which was progressive (actually described at the time by the technically correct term "sequential") and the 405-line system which started as 5:4 and later changed to 4:3. The 405-line system adopted the (at that time) revolutionary idea of interlaced scanning to overcome the flicker problem of the 240-line with its 25 Hz frame rate. The 240-line system could have doubled its frame rate but this would have meant that the transmitted signal would have doubled in bandwidth, an unacceptable option as the video baseband bandwidth was required to be not more than 3 MHz.
When was the Baird system discontinued?
February 1937

Hayek is widely recognised for having introduced the time dimension to the equilibrium construction and for his key role in helping inspire the fields of growth theory, information economics, and the theory of spontaneous order. The "informal" economics presented in Milton Friedman's massively influential popular work Free to Choose (1980), is explicitly Hayekian in its account of the price system as a system for transmitting and co-ordinating knowledge. This can be explained by the fact that Friedman taught Hayek's famous paper "The Use of Knowledge in Society" (1945) in his graduate seminars.
What is the name of the book Friedman released in 1980?
Free to Choose

The main active ingredient of beer is alcohol, and therefore, the health effects of alcohol apply to beer. Consumption of small quantities of alcohol (less than one drink in women and two in men) is associated with a decreased risk of cardiac disease, stroke and diabetes mellitus. The long term health effects of continuous, moderate or heavy alcohol consumption include the risk of developing alcoholism and alcoholic liver disease. A total of 3.3 million deaths (5.9% of all deaths) are believed to be due to alcohol. Alcoholism often reduces a person's life expectancy by around ten years. Alcohol use is the third leading cause of early death in the United States.
What is beers primary active ingredient?
alcohol