Standard deviation is the square root of variance, but variance is given by mean, so divide by number of samples. That is : 38.5/10 = 3.58. But standard deviation equals the square root of variance, so SD = the square root of 3.85 which is 1.96.
The virginal(s): The virginal, also called virginals, usually has a rectangular case with the keyboard across the wide side. As with the spinet, the strings run side-to-side relative to the player. Again, it saves on wallspace, and again they rate their own FAQ. Virginals were fairly early, 15th and16th centuries.
The spinet piano weight, dimensions and price. The spinet is a small keyboard musical instrument which has one row of strings and one manual. The spinet piano weight is 300-500 lbs. It is twice lighter than upright, which is 900 pounds approximately. Unlike the other types of a harpsichord, spinet strings are tensioned diagonally (from left to right). This instrument has been known since 16th century.