Answer:
a) The confidence interval is
.
Step-by-step explanation:
We have to calculate a confidence interval (CI) of a difference of proportions.
For the existing procedure, the proportion is:

For the new procedure, the proportion is:

To calculate the CI, we need to estimate the standard deviation

For a 90% CI, the z-value is 1.64.
Then, the CI is:

The answer to the question
I believe is your answer
Because u plug in -2 to all x
F(x)= (-2)^2-9(-2)+2
F(x)=4+18+2
F(x)=24
Sqr (x2 - x1)^2 + (y2 - y1)^2
Sqr (-4-0)^2 + (2+5)^2
Sqr (16) + 49 = sqr 65
I got around 8.
(I might did something wrong, idk)