What are four ways to tell different kindsof sharks apart?

Question

I need to find four ways to tell different sharks apart for science hw!!!!!

Answer 1

number of gills
teeth
shape
coloration

(just guessing)

Answer 2

Four ways to tell different kinds of sharks apart:
1.Body size(length and weight if possible)
2.Diet(what they eat)
3.Colour of the body
4.Location-where they are dominant(found the most)