Photo #2:
A: Ducts of the glands
B: Secretory parts of the glands (the secretory cells are bigger and lighter than those making the wall of the duct. Be careful, the little dark dots in the bottom photo are nuclei of cells).

The sweat glands are classified as simple convoluted tubular glands.
The duct connecting the secretory part to the lumen do not ramify (if it did ramify, the diameter of the sections through the duct would vary widely - it is not the case here: -->simple)
The duct is twisted onto itself (if the duct was straight, only one section through the duct would be seen, not 9: --> convoluted).
The secretory part is shaped like a tube (depending on how the tube is cut one will see circular or elongated sections - the tube also is twisted which explains why 4 sections of it are seen--> tubular).