Give answer if you are sure onlyDoes the formula for confidence interval CI both when the standard deviation is known and unknown is different for large and small sample sizes?

If the public debt of a country in 2009 was $10432000000000 and the budget for 2010 was in deficit by $201645000000, what was the public debt in 2010? do not include commas in your answer.

Polynomial that can be factored as (3x-4)(3x+4)

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10