A platypus is a mammal that lays eggs. It is not at all related to ducks (and its bill is not really similar to a duck's bill, either). Apart from laying eggs, it shares all other mammalian characteristics. Egg-laying mammals are known as monotremes.
Although the platypus has webbed feet and the bill of a duck, it is a warm blooded mammal.
it is a semi aquatic mammal
If you mean the "platypus," no, it is not a bird. It is a mammal.
It is a mammal
No. A platypus is a semi-aquatic mammal that lays eggs.
Quite simply, the platypus is a mammal, not a bird. It has fur instead of feathers, and it feeds its young on mothers' milk.
The platypus is a mammal. Although it lays eggs in a burrow, and hunts for food in the water, it is a warm-blooded mammal that breathes using lungs, not gills. It also feeds its young on mothers' milk, something which no fish does.
A platypus does not have wings. It is a mammal, not a bird, and bats are the only mammals that can truly fly.
A platypus is a mammal and it has a duck-like bill and duck-like webbed feet.
No features suggest it is a bird. It is a mammal. The bill of a platypus serves a quite different function to that of any bird, as bird do not have electroreceptors in their bills. Platypuses do lay eggs, but even the eggs are quite different to those of a bird.
A platypus is a monotreme, which is an egg-laying mammal.
A penguin is a bird or a vertibrate animal. Mammals are animals which only give birth to live young (with the sole exception of the platypus, which lays eggs).
The platypus is a monotreme mammal.
The platypus is not a reptile - it is an egg-laying mammal.