please help--tracks, sectors, VTOC, and disk geometry

[jutland1916@hotmail.com]

Hi,

I have some questions about DOS 3.3 disk geometry. I've looked at many
FAQs and online documentation, including those at CSA2, and not found
the specific information I need.

Here are my questions:

Moving from the center to the edge of the disk, are tracks numbered in
ascending or descending order? Is track 34 closest to the center of the
disk or closest to the outer edge?

Moving clockwise around the disk, are sectors numbered 0-15 or 15-0?

I have a disk image whose VTOC indicates that the last allocated track
was 22, moving inward ($16, $01), yet there is good data beyond that
(at tracks 33-34). How can that happen?

Does the VTOC retain a record of "erased" data on the disk that has not
yet been overwritten?

Why are the VTOC and Catalog sectors always at track 17? Is there a
mechanical reason for this, something related to the position of the
read/write head, given that it's the middle track of the drive?

Thank you very much in advance.

Mark