Which of the following organisms is an example of nekton?

The organism that could be considered as an example of a nekton is: Dolphin

Nekton is aquatic animals that have the capability to move independently within water currents.
Nektons are able to do this because they've developed their own unique mechanism to detect their own way within the currents (such as using biosonar or Antenne) 

Texture and composition are different because they are not the same aspect. texture has to do with feel and so on, where as composition is the chemical makeup which you cant touch like you can texture.

The purpose of a lab is to do your "expirements" the importance of the topic is so you can now what the story is about and the last one is because no one is me with my question ( what is 3 over 4 x - 9 = 27 maybe you can )