Molecules Speed Up because the other three options only occur when the temperature is decreased.
        
                    
             
        
        
        
A boiling pot of water (the water travels in a current throughout the pot), a hot air balloon (hot air rises, making the balloon rise) , and cup of a steaming, hot liquid (hot air rises, creating steam) are all situations where convection occurs. 
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Answer:
answer is option 4
Explanation:
you have to use option 4 because u need to find out initial velocity (Vi)
 
        
             
        
        
        
The load is the weight of the rock that Jonathan lifts:

The effort instead is the force applied in input to the lever in order to lift the rock:

So, the ratio between load and effort for this exercise is

So, the ratio is 10:1.
 
        
             
        
        
        
Answer:
C
Explanation:
An element is a pure substance that can not be broken down into anything simpler
A compound in also a pure substance held together in fixed proportion through chemical bonds