<em><u>T</u></em><em><u>H</u></em><em><u>E</u></em><em><u> </u></em><em><u>E</u></em><em><u>Q</u></em><em><u>U</u></em><em><u>A</u></em><em><u>T</u></em><em><u>I</u></em><em><u>O</u></em><em><u>N</u></em><em><u> </u></em><em><u>I</u></em><em><u>S</u></em><em><u> </u></em><em><u>A</u></em><em><u> </u></em><em><u>TRINOMIAL</u></em><em><u> </u></em><em><u>B</u></em><em><u>E</u></em><em><u>C</u></em><em><u>A</u></em><em><u>U</u></em><em><u>S</u></em><em><u>E</u></em><em><u> </u></em><em><u>I</u></em><em><u>T</u></em><em><u> </u></em><em><u>H</u></em><em><u>A</u></em><em><u>V</u></em><em><u>E</u></em><em><u> </u></em><em><u>T</u></em><em><u>H</u></em><em><u>R</u></em><em><u>E</u></em><em><u>E</u></em><em><u> </u></em><em><u>T</u></em><em><u>E</u></em><em><u>R</u></em><em><u>M</u></em><em><u>S</u></em><em><u> </u></em><em><u>I</u></em><em><u>N</u></em><em><u> </u></em><em><u>I</u></em><em><u>T</u></em>
The margin of error for a sample proportion is given by

where:

is the z score associated with the confidence level, p is the sample prortion and n is the sample size.
We assume a confidence level of 95%, then
p = 52% = 0.52 and n = 2251
Therefore, margin of error =

The the interval that is likely to contain the true population proportion is between 49.9% and 54.1%.
Answer:
a = 30 degrees; b = 60 degrees; and c = 105 degrees.
Step-by-step explanation:
Angle a and the 30 degree angle are vertical angles and thus are equal.
Since the interior angles of a triangle always add up to 180 degrees, 30 + b + 90 degrees = 180 degrees, so that b must be 60 degrees.
Angle c and the 75 degree angle are straight angles, and so their sum must be 180 degrees. Thus, c = 105 degrees.
subtracting 9.1 - 12.9 is -3.8