Answer:
Weather conditions
Explanation:
Food can be limited based on location, however, scientists can control what kind of food it is. Soil can be tested and experimented on. There can be a lot of it and different kinds. Space is fought over because of territories and is limited compared to how many people and animals there are. Weather is not something that can be controlled in an experiment since it is sporadic. 
 
        
                    
             
        
        
        
Answer:
recreational - enjoyment i.e. weed, alcohol (legal)
shrooms, lsd (illegal)
liver or lung failure
stimulant- helps asthma and other things example. dexedrine
the effects of taking stimulants is loss of appetite, increased heart rate, elevated blood pressure and body temperature, interrupted sleep patterns, panic, hallucinations, and irritability.
also a drug is a medicine or other substance which has a physiological effect when ingested or otherwise introduced into the body.
 
        
                    
             
        
        
        
Movement of cell against concentration gradient is called a.osmosis
        
             
        
        
        
Explanation:
choose the correct possesive noun a) Jone's boat is broken b) Jones' boat is broken c)Jones's boat is 
<em> </em><em>h</em><em>e</em><em>y</em><em> </em><em>g</em><em>u</em><em>s</em><em>s</em><em>a</em><em> </em><em>h</em><em>o</em><em> </em><em>a</em><em>b</em><em>i</em><em> </em><em>t</em><em>k</em><em>☹</em>
 
        
                    
             
        
        
        
B. It is a form of passive transport.