Energy in ecosystems must be continuously supplied by the sun  as the warmth from the sun allows plants to grow plus photosynthesis depends on the sun's energy also. Animals also depend on the sun for warmth to survive (or else hibernate). Also, the sun powers the water cycle, the carbon cycle and the nitrogen cycle
 
        
             
        
        
        
ATP is Adenosine Triphosphate. ATP consists of an adenosine molecule bonded to 3 phosphate groups in a row. This occurs when a molecule of adenosine diphosphate ( ADP ) uses the energy released during cellular respiration bond with a 3rd phosphate group, becoming a molecule of ATP
 
        
             
        
        
        
Answer:
1) Organisms in this domain can be unicellular or multicellular - Eukarya
2) Organisms in this domain are unicellular and are often found in extreme environments - Archaea
3) Organisms in this domain have cells that contain a nucleus - Eukarya
Explanation:
All living organisms were classified into a large group consisting of three types of organisms called DOMAIN. It is the highest taxonomic rank of organisms. The three domains that life was classified into are: Archaea, Bacteria and Eukarya.
The domain Archaea contains organisms that are unicellular and prokaryotic i.e. they do not have a membrane-bound nucleus. The organisms in this domain are characterized by their ability to survive in harsh environmental conditions e.g hot temperatures etc
The domain Bacteria also consists of unicellular and prokaryotic organisms. They contain cell walls in their cells made up of peptidoglycan unlike domain Archaea and Eukarya. 
The domain Eukarya consists of organisms that are both unicellular and multicellular and strictly eukaryotic i.e. possess a membrane bound nucleus that houses their genetic material. They are divided into Kingdoms: Protista, Plantae, Animalia and Fungi.
 
        
                    
             
        
        
        
Answer: The percentage would be 19%, 51% and 30%.
Explanation:
Since we have given that 
Number of food eaten by X = 57
Number of food eaten by Y = 153
Number of food eaten by Z = 90
Total number of food eaten = 
So, Food percentage of flock X = 
Food percentage of flock Y = 
Food percentage of flock Z = 
Hence, the percentage would be 19%, 51% and 30%.