Food fryers manufactured by a company that supplies food trucks can fry a mean of 132.4 pounds of food per hour with a standard deviation of 3.9
pounds per hour. In a given hour, how much food would 99.7% of these fryers
fry?
A. 124.6 pounds per hour to 140.2 pounds per hour
B. 128.5 pounds per hour to 136.3 pounds per hour
C. 120.7 pounds per hour to 144.1 pounds per hour
D. 116.8 pounds per hour to 148.0 pounds per hour

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.