Answer:
Due to mixing of particles present in the upper layer of limestone with sandstone during deposition.
Explanation:
The parent layer was limestone layer which is older than sandstone layer. This sandstone layer spreads on the limestone layer because of wind. The wind moves these sandstone from other region and their deposition occurs on the limestone layer. During deposition of sandstone, some particles of limestone which are present at the surface mixes with the sandstone so that's why in sandstone layer, small and weathered pieces of limestone are present.
 
        
             
        
        
        
The principle of competitive exclusion states that two species cannot coexist in the same habitat.
<h3>What is 
 competitive exclusion?</h3>
The competitive exclusion principle, often known as Gause's law, is a theory in ecology that holds that two species competing for the same scarce resource cannot coexist at constant population levels. One species will eventually outnumber all others if it has even a modest edge over the others. This results in the weaker competitor's extinction or an evolutionary or behavioral shift in favor of a different ecological niche. The adage "complete competitors cannot coexist" is a paraphrasing of this idea.
Although he never created it, Georgy Gause is traditionally credited with coming up with the competitive exclusion principle. The natural selection theory put forward by Charles Darwin already incorporates the concept.
The status of the principle has fluctuated during the course of its history between
To learn more about  competitive exclusion from the given link:
brainly.com/question/2083056
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Answer:
C
Explanation:
Recycling a metal can so it can be reused.
 
        
             
        
        
        
D because gravitational force cannot pull or push