The name is Copper(II) Oxide and/or Cupric Oxide.
Cu is Copper and O is Oxygen.
Usually when the Oxygen ion is placed after another, it's name is Oxide.
The different types of microscopes are all necessary because not all experiments require the same level of magnification. For dissections low magnification is sufficient, so a dissecting microscope works very well, while for viewing single cells the 1000 fold magnification of a compound light microscope is more accurate.