There are 20 pieces.
many pieces
45988064938320
Usually one, unless the piece is in pieces.
32?
Depends on how many pieces you cut it into. It could be a single piece or dozens if you mince it.
an a2 has 6 pieces of a4
4 pieces of A4 fit on one piece of A2.
12 pieces.
it depends on the dementions
Many such pieces are called etudes.
4 parts
how many ounces equals a piece of paper