Kinetic energy = 0.5*M*V^2 
 Q7-
 
0.5*3*(2^2)= 6J
Q8a- 
0.5*2*(2^2)= 4J
0.5*4*(3^2)=18J 
the second ball has more kinetic energy.
Q8b-
at the max height, all the kinetic energy is converted to potential energy, 
gravitational potential energy is = M*g*h
that theory would apply if you wanted to work out the maximum height achieved if the balls were thrown upward by rearranging. But, we are simply working out which ball will have more potential energy so:
First ball:
2kg*9.81(g)*10m = 196.2J
Second ball
4kg*9.81*10m= 392.4J
The second ball has more potential energy 
        
             
        
        
        
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Answer:
Mouth: site where mechanical digestion takes place
Stomach: A mixture of chemical etc...
Esophagus: At this site, muscles are contracted to falicilitate peristalsis 
 
        
             
        
        
        
Answer:
HEREDITY ONLY:
none
GENETIC VARIATION ONLY:
none
BOTH:
all
Explanation:
In all the organism that reproduce sexually, produced offspring are genetically varied. As this genetic variation continues, it also leads to hereditary evolution of organism through gene flow from one generation to other. Therefore, the processes of DNA replication, crossing over, chromosome separation and alignment etc. ensure flow of genes from one generation to the next. This does not happen in organisms reproducing asexually.