Pressure is force over area. So assuming your cube is at rest and on earth, then the force is mass x gravity and the pressure is mass x gravity / area.
A string quartet is made up of four musicians playing two violins, a viola, and a cello. These are all string instruments played either by plucking the strings or using a bow. The violins are the smallest and typically play the higher notes. The viola and cello are larger instruments and play the lower notes.
The string quartet developed in Germany and Austria in the years 1750-80 from the divertimento, chamber music that could feature any number of players and was intended as a light diversion or background music.