35 parts per thousand
Sea water. Seawater is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of approximately 3.5%, or 35 parts per thousand. This means that for every 1 litre (1000 mL) of seawater there are 35 grams of salts (mostly, but not entirely, sodium chloride) dissolved in it.
 
        
             
        
        
        
Temperature, pressure and composition. 
        
                    
             
        
        
        
I have no clue, there is nothing else here to support your question.
        
             
        
        
        
Since nicotine is a form of a stimulant drug, in cigarette smoke it can cause addiction.
Many people who smoke are actually addicted to smoking, and cannot stop doing so easily, which is similar to how drug addicts behave when it comes to using drugs. 
        
             
        
        
        
Answer:
The correct answer will be option-A
Explanation:
Colchicine is the drug that prevents the assembly of the mitotic spindles which halts or stops the cell cycle.
The colchicine acts by inhibiting the microtubule polymerization thus mitotic spindles which takes place after the condensation of the chromosomes during prophase and pre-metaphase.
This acts as checkpoint which can halt the cell cycle at the phase of chromosome condensation.
Thus, option-A is the correct answer.