Yes, they are worm blooded and feed on milk.
ducks are not mamals beacause they lay eggs
yes
All mammals have a vertebra, therefore are part of the 'Vertebrate' group.
Yes
a pod
Yes.
yes sirree bob, pretty much all mammmals have gallbladders.
pigs and dophins
bottlenose dolphins
yes. on the top of their heads
No, only mammmals have nipples, or furthermore, breasts.
Smooth, slightly rubbery skin