European art music is largely distinguished from many other non-European and popular musical forms by its system of staff notation, in use since about the 16th century. Western staff notation is used by composers to prescribe to the performer the pitches (e.g., melodies, basslines and/or chords), tempo, meter and rhythms for a piece of music. This leaves less room for practices such as improvisation and ad libitum ornamentation, which are frequently heard in non-European art music and in popular music styles such as jazz and blues. Another difference is that whereas most popular styles lend themselves to the song form, classical music has been noted for its development of highly sophisticated forms of instrumental music such as the concerto, symphony, sonata, and mixed vocal and instrumental styles such as opera which, since they are written down, can attain a high level of complexity.
Classic music can a attain a high level of what?
complexity

This annexation was one of the direct causes of the brief and bloody War of the Reunions whose outcome left the French in possession. The French annexation was recognized by the Treaty of Ryswick (1697). The official policy of religious intolerance which drove most Protestants from France after the revocation of the Edict of Nantes in 1685 was not applied in Strasbourg and in Alsace, because both had a special status as a province a l'instar de l'etranger effectif (a kind of foreign province of the king of France). Strasbourg Cathedral, however, was taken from the Lutherans to be returned to the Catholics as the French authorities tried to promote Catholicism wherever they could (some other historic churches remained in Protestant hands). Its language also remained overwhelmingly German: the German Lutheran university persisted until the French Revolution. Famous students included Goethe and Herder.
When was the French annexation recognized by the Treaty of Ryswick?
1697

The Russian Revolution is the series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. Following the abdication of Nicholas II of Russia, the Russian Provisional Government was established. In October 1917, a red faction revolution occurred in which the Red Guard, armed groups of workers and deserting soldiers directed by the Bolshevik Party, seized control of Saint Petersburg (then known as Petrograd) and began an immediate armed takeover of cities and villages throughout the former Russian Empire.
What happened when Nicholas II was removed from power?
the Russian Provisional Government was established.