Answer:
All the offsprings would be heterozygous purple colored flower
Explanation:
Given 
Purple color flower is dominant over white color flower
Let the allele for purple color of flower be represented by "P"
and the allele for white color flower be represented by "p"
A pea plant that is homozygous purple-flowered is crossed with a pea plant that is white-flowered. 
Genotype of homozygous purple-flower is "PP"
and Genotype of homozygous white-flower is "pp"
Cross between PP and pp produce the following offspring
PP * pp
Pp, Pp , Pp , Pp
All the offsprings would be heterozygous purple colored flower
 
        
             
        
        
        
The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
 
        
                    
             
        
        
        
Oxygen gas contributes to the green house effect
        
             
        
        
        
TO. YOUR. BRAIN. have a nice day?
 
        
             
        
        
        
Answer B did this a few ago