Answer:
The 85% onfidence interval for the population proportion of new car buyers who prefer foreign cars over domestic cars is (0.151, 0.205).
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:
Sample of 421 new car buyers, 75 preferred foreign cars. So 
85% 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 85% onfidence interval for the population proportion of new car buyers who prefer foreign cars over domestic cars is (0.151, 0.205).
In this question, the first information that we get is that Kayla spent half of her weekly allowance in clothes. On cleaning the oven Kayla gets $4. Finally Kayla is left with $12.
Let us assume that the weekly allowance of Kayla = x
Amount of allowance saved after buying clothes = x/2
Then we can go for the equation
x/2 + 4 = 12
x + (4 * 2) = 12 * 2
x + 8 = 24
x = 24 -8
= 16
So we can now see that the weekly allowance of Kayla is $16
Answer: -2
Step-by-step explanation: The line has a slope of -2/1, which is just -2.