Answer:
The 95% confidence interval for the percent of all black adults who would welcome a white person into their families is (0.8222, 0.8978).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
For this problem, we have that:
323 blacks, 86% of blacks said that they would welcome a white person into their families. This means that 
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 95% confidence interval for the percent of all black adults who would welcome a white person into their families is (0.8222, 0.8978).
Okay this equation really says is what is 30% of 248.
So, lets convert 30% to a fraction, 3/10 which is easier to work with.
All you have to do now is get out a calculator and do 248 *3/10 (or .3) and get 74.4
So subtract 74.4 and get
173.6
A = 1.5
B = -1/3
C = -4/3
A is a positive so there is only one possibility
B is in between 0 and -1, so it has to be -1/3
C is below -1 and so its the improper fraction
the answer is D, you divide 8 by 16 you get 2 in below the division sign, cosine 180 is -1 , sine 180 is zero so the imaginary number cancels out leaving only -1 multiplied by 2 equals -2 then cosine and sine 95 equal negative the cosine and sine of 275 you take the negative sign common factor divide it by the negative sign of 2 and you get the answer is d
