Answer: mathematics
Explanation:
Mathematics is the study of quantity, space, structure of a concerned entity or population size. A scientific experiment may be based on the analysis of variables must be having large sample size. Therefore, quantitative estimation  of the results is required. Hence, a scientist requires mathematics to interpret the results of a scientific experiment. 
 
        
                    
             
        
        
        
It will be half 
A normal cell contains 46 chromosomes.
Gametes only contain 23 because they will be paired with an opposite gamete cell upon fertilisation 
- Egg contains 23 
- Sperm contains 23
Together they make the normal amount of 46
        
             
        
        
        
Answer:
The disadvantages of the given instance are mentioned below.
Explanation:
This analysis seems to be a tool device used to evaluate the proportion of the population. 
<u>Disadvantages:</u>
- The effectiveness is dependent on a significant portion of the number of people is being recorded. 
- Animal marks may have a drastic impact on either the animals.
- This approach does indeed have a certain drawback because that's not a very suitable technique.
 
        
             
        
        
        
Explanation:
Oxygen is the answer. (option B)
 
        
             
        
        
        
The correct answer is B, I know this because none of the other answers are even reasonable. For example-
A is wrong because the size of elephant tusk has not changed over time, elephant tusk just grow...
C is wrong because it makes no sense to hunt elephants with no tusk :/
D is completely wrong because tusk have nothing to do with reproduction, those are two completely separate bodily functions.........