The phrase "harmony is vertical" means that                a.  harmony involves notes that sound at the same time.      b.  harmony includes every note in an octave.      c.  the singers in a harmony improvise notes from up and down a scale.      d.  notes in a harmony only increase in pitch.

Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the correct position in the answer box. release your mouse button when the item is place. if you change your mind, drag the item to the trashcan. click the trashcan to clear all your answers. drag each phase of mitosis to the correct description.