If all three parameters are used, they are specified in the following form: [frame size][scanning system][frame or field rate] or [frame size]/[frame or field rate][scanning system].[citation needed] Often, frame size or frame rate can be dropped if its value is implied from context. In this case, the remaining numeric parameter is specified first, followed by the scanning system.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Which two parameters can be dropped if its value is implied from context?
Ah, so.. frame size or frame rate

The instruments currently used in most classical music were largely invented before the mid-19th century (often much earlier) and codified in the 18th and 19th centuries. They consist of the instruments found in an orchestra or in a concert band, together with several other solo instruments (such as the piano, harpsichord, and organ). The symphony orchestra is the most widely known medium for classical music and includes members of the string, woodwind, brass, and percussion families of instruments. The concert band consists of members of the woodwind, brass, and percussion families. It generally has a larger variety and amount of woodwind and brass instruments than the orchestra but does not have a string section. However, many concert bands use a double bass. The vocal practices changed a great deal over the classical period, from the single line monophonic Gregorian chant done by monks in the Medieval period to the complex, polyphonic choral works of the Renaissance and subsequent periods, which used multiple independent vocal melodies at the same time.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): A symphony orchestra includes members of the string, woodwind, percussion and what other family of instruments?
Ah, so.. brass

During the later stages of World War II, the entire Cold War, and to a lesser extent afterwards, uranium-235 has been used as the fissile explosive material to produce nuclear weapons. Initially, two major types of fission bombs were built: a relatively simple device that uses uranium-235 and a more complicated mechanism that uses plutonium-239 derived from uranium-238. Later, a much more complicated and far more powerful type of fission/fusion bomb (thermonuclear weapon) was built, that uses a plutonium-based device to cause a mixture of tritium and deuterium to undergo nuclear fusion. Such bombs are jacketed in a non-fissile (unenriched) uranium case, and they derive more than half their power from the fission of this material by fast neutrons from the nuclear fusion process.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What does non-fissile mean?
Ah, so..
unenriched