Next, Mendel took the F1 progeny and allowed them to self-fertilize. In the resulting F2 generation, 3/4 showed the dominant phenotype, and 1/4 showed the recessive phenotype. ... 1 out of 3 round pea plants from the F2 generation were true-breeding and produced only offspring with round peas.
 
        
                    
             
        
        
        
The air gap is filled with gas which increases the insulation between the glass pieces. Double glazed windows are highly efficient, reducing your heat loss or gain by up to 30% when compared to single-glazed windows.
        
             
        
        
        
Answer:
Wood
Explanation:
Takes time to reproduce it.