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 standard structure for a string quartet is four movements, with the first movement in Sonata form, Allegro, in the tonic key; second movement is a slow movement, in a related key; third movement is a Minuet and Trio, in the tonic key; and the fourth movement is often in Rondo form or Sonata rondo form, in the tonic key.