Stomata are tiny pores present in the leaf that allows gas exchange and is where water vapour leaves plants and carbon dioxide enters. Special cells called guard cells present in the stomata, control each pore's opening or closing. When stomata are open, transpiration rates increase; when they are closed, transpiration rates decrease.
        
                    
             
        
        
        
G1, S, G2, Mitosis, Cytokinesis
Just did this yesterday lol hope it helps
        
                    
             
        
        
        
The energy before and after a process must be the same.
        
             
        
        
        
After two half-lives or 60 years, 7.5 g of the element will be left. 
<u>Explanation:</u>
<u>Half-life:</u>
- In simple words, Half-life can be defined as the amount of time needed for a quantity to fall to half its value as contained at the beginning of the time period. 
- In this problem the half-life of the element is thirty years, then after thirty years half of the sample would have decayed and half would be left as it is. 
- After thirty years (The first half-life ) 30 /2 = 15 g declines and 15 g remains disappeared. 
- And after another sixty years (The two half-lives) 15 /2 = 7.5 g declines and 7.5 g remains disappeared. 
- After two half-lives or 60 years, 7.5 g of the element will be left.