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 
        
             
        
        
        
I would say it is a hydrogen bond
        
                    
             
        
        
        
Shock Treatment (or Fish Fry) Presently several hundred feet of electrified canal water is all that stands between the most advanced front of Asian carp and a free run to the open waters of Lake Michigan.
Hope this helps :)
        
             
        
        
        
The anthers are in the elevated position so that the pollinators will be attracted towards it, and that the pollen grains are easily carried away by the agents of pollination. The proper pollination is essential for the process of fertilization.
Hope this helps:)