Similarity between fish and tadpole is

Write one example for each of the following in the space provided:
$(a)$ Cold-blooded animal.
$(b)$ Warm-blooded animal.
$(c)$ Animal possessing dry and cornified skin.
$(d)$ Dioecious animal.

Ascaris and Cockroach resemble each other in

Which one feature is common to leech,cockroach and scorpion?

Water circulatory system is found in:
$I.$ Sponge
$II.$ Hydra
$III.$ Annelida
$IV.$ Starfish
$V.$ Arthropoda
Choose the correct option.

The difference between male and female $Anopheles$ occurs in: