<u>The levels of organisation are</u>
 Domain: Eukarya
Kingdom Animalia
Phylum :Chordata
Explanation:
They all share these levels of organisation because;
<u>for  the Domain Eukarya, they have;</u> 
→multi-cellular cells containing   nucleus; and  other membrane bound organelle.e.g Mitochondrial.
→their  DNA located in the   nucleus  packaged as linear chromosomes bounded by histone proteins.
→mode of reproduction which is  sexual.
They share Kingdom Animalia because; 
→they have multi-cellular, specialised cells, bounded by plasma membranes.
→they have specialized  tissues, organs, and system.
→they all undergo <u>heterotrophic mode of nutrition</u> <u>as evident in the question 'that they must consume plants and animals as source of energy'</u>
<u>→they exchanged communication by nervous ssytem and </u>
<u>→ use homeostatic mechanisms to regulate water balance of the body through the kidney.</u>
<u>→Humans,Rabbits,and whales are</u><u> VIVIPAROUS; they give birth to young ones alive.</u>
→Most fishes lay eggs to reproduce, they are said to be <u>Ovoviviparous.</u>
<u>They belong to phylum Chordata because ;</u>
<u>→they  all have noto chord;</u> which serve as template for axial skeleton.
<u>dorsal hollow nerve cord </u>-template for the brain and spinal cord
<u>→pharyngeal slits- </u>templates for gill aches in bony fishes and components of inner ear in land animals.
<u>→ tail</u> length varies  in these organisms.