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.
Neck woods â mahogany & maple. The wood used for the neck needs to provide good longitudinal strength and carve easily. The vast majority of acoustic guitar necks are made from mahogany. However the description âmahoganyâ is pretty vague since there are two, completely different, species of wood commonly called mahogany.