Answer:
The Cell.
Explanation:
Living organisms are composed of single or multiple cells. The cell is termed the building block of life. Single cell organisms are called unicellular while multiple cell organisms are called multicellular. A single cell organism is capable of performing all the basic functions of life like reproduction, respiration etc 
 
        
             
        
        
        
Answer:
Polar Bears feed on seals. So, polar bears and seals share a prey predator relationship.  If one species cannot then adapt an appropriate defense, they may go extinct. In this way, the predator prey relationship often forms and "evolutionary arms race", in which eats species rapidly evolves to counter the other.
Explanation:
Complete the paragraph based on this food web: Polar bears feed on seals. So, polar bears and seals share a _prey predator_.Climate change has caused ice caps to melt in colder regions where polar bears live. This change has caused them to hunt less. This situation will lead to_?extinction?_ 1 prey-predator relationship mutual relationship parasitic relationship. 2 less biomass in the quaternary level increased biomass in the quaternary level less biomass in the primary level. 
If one species cannot then adapt an appropriate defense, they may go extinct. In this way, the predator prey relationship often forms and "evolutionary arms race", in which eats species rapidly evolves to counter the other.
 
        
             
        
        
        
Salutations!
A surface wave on ocean surface is an example of an _______.
A surface wave on ocean surface is an example of an mechanical wave. Mechanical waves are waves that need a substance of medium for the wave's propagation is called mechanical wave.
Hope I helped :D
        
             
        
        
        
Answer:
Superposition
Explanation:
Sedimentary rocks are deposited one on top of another. The youngest layers are found at the top of the sequence, and the oldest layers are found at the bottom.