Which of the following is a free-living flatworm?

What is prominently observed in Planaria?

Consider the following characters $:-$
$1.$ Bilateral symmetry
$2.$ Acoelomate
$3.$ Incomplete digestive system
$4.$ Mostly endoparasites
Select the correct group of phylum with its corresponding animal for the above-given characters $:-$

Identify the given Platyhelminthes organisms.

What is observed in Platyhelminthes,in contrast to Annelida?

The gut is present in all of the following taxonomic groups of Platyhelminthes,except for one. Identify the group in which it is absent.