Answer:
The correct option is B.
Step-by-step explanation:
The given equation are


On solving both the equation, we get




Put this value in the given equation.




The solution of the given system of equation is

The best approximation of the exact solution is (1.3,2.3). Therefore the correct option is B.
I'm not quite sure but I believe the answer to your question is 4 sides
Answer: 40000
Step-by-step explanation:
The formula to find the sample size is given by :-
, where p is the prior estimate of the population proportion.
Here we can see that the sample size is inversely proportion withe square of margin of error.
i.e. 
By the equation inverse variation, we have

Given :


Then, we have

Hence, the sample size will now have to be 4000.
I believe D will be the correct answer.