At the time the store was introduced, purchased audio files used the AAC format with added encryption, based on the FairPlay DRM system. Up to five authorized computers and an unlimited number of iPods could play the files. Burning the files with iTunes as an audio CD, then re-importing would create music files without the DRM. The DRM could also be removed using third-party software. However, in a deal with Apple, EMI began selling DRM-free, higher-quality songs on the iTunes Stores, in a category called "iTunes Plus." While individual songs were made available at a cost of US$1.29, 30¢ more than the cost of a regular DRM song, entire albums were available for the same price, US$9.99, as DRM encoded albums. On October 17, 2007, Apple lowered the cost of individual iTunes Plus songs to US$0.99 per song, the same as DRM encoded tracks. On January 6, 2009, Apple announced that DRM has been removed from 80% of the music catalog, and that it would be removed from all music by April 2009.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What was the name of the DRM system originally used by Apple and iTunes?
Ah, so.. FairPlay

The British adopted "effective ceiling", meaning the altitude at which a gun could deliver a series of shells against a moving target; this could be constrained by maximum fuse running time as well as the gun's capability. By the late 1930s the British definition was "that height at which a directly approaching target at 400 mph (=643.6 km/h) can be engaged for 20 seconds before the gun reaches 70 degrees elevation". However, effective ceiling for heavy AA guns was affected by non-ballistic factors:
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who adopted the use of the term, effective ceiling?
Ah, so.. The British

American concerns that they had fallen behind the Soviet Union in the race to space led quickly to a push by legislators and educators for greater emphasis on mathematics and the physical sciences in American schools. The United States' National Defense Education Act of 1958 increased funding for these goals from childhood education through the post-graduate level.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): The United States' National Defense Education Act was established in what year?
Ah, so..
1958