If the mean of a dataset is 25 and its standard deviation is 1.6, then. 1  68% of the values in the dataset will lie between MEAN-1SD (25-1.6=23.4) and MEAN+1SD (25+1.6=26.6) 2  99% of the values will lie between MEAN-3SD (25-4.8=20.2) and MEAN+3SD (25+4.8=29.8).
For the first time, during the Classical period most of the important stylistic advances that occurred can be observed most clearly in the instrumental forms: the symphony, concerto, sonata, and in instrumental chamber music (e.g., the Beethoven string quartets).
In addition to referring generally to all Western art music from the Medieval era to the 2000s, the term Classical music also refers more specifically to the music from the 1750s to the early 1830sâthe era of Mozart and Haydn.