Is shown. The graph of f(x) = 72 - 24 - 3
For which values of c is f(x) decreasing?
(3, 0)
YA
61
5
4
(-1, 3) U (3, 00)
3
2
1
(-1, 3)
2
3
4
10
5
6 X
5
4
.2
- 2
-1
(1, 3) U (3, 0)
13
-4
-9
iready diognostco

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.