Which among the following phyla is exclusively marine?

Identify the phylum of kingdom Animalia in which the animal has:
$(a)$ $A$ pseudocoelom
$(b)$ $A$ water-driven tube system
$(c)$ Jointed legs
$(d)$ Pores in the body leading to a canal system
$(e)$ Notochord at some stages of their life.

Amphibians do not have which of the following?

Give reasons:
$(a)$ Animals of phylum Platyhelminthes are called flatworms.
$(b)$ Bryophytes are called amphibians of the plant kingdom.
$(c)$ Fungi are called saprophytes.
$(d)$ Bacteria and tapeworms are very different in their body design.
$(e)$ Plants like Pinus and deodar are called gymnosperms.

Give reasons for the following:
$(a)$ Echidna and Platypus lay eggs but are considered as mammals.
$(b)$ Birds have pneumatic bones.

Mention any three major differences between Porifera and Coelenterata.