Answer:
99.7% of customers have to wait between 8 minutes to 30 minutes for their food.
Step-by-step explanation:
We are given the following in the question:
Mean, μ = 18 minutes
Standard Deviation, σ = 4 minutes
We are given that the distribution of amount of time is a bell shaped distribution that is a normal distribution.
Empirical Formula:
- Almost all the data lies within three standard deviation from the mean for a normally distributed data.
- About 68% of data lies within one standard deviation from the mean.
- About 95% of data lies within two standard deviations of the mean.
- About 99.7% of data lies within three standard deviation of the mean.
Thus, 99.7% of the customers have to wait:

Thus, 99.7% of customers have to wait between 8 minutes to 30 minutes for their food.
Rewrite in slope intercept from y=mx+b y=1-3x+11/3
Probability hit=40%=4/10
probability no hit=1-p (hit)=1-4/10=6/10
probability= p(hit)+p(hit)+p(hit)+p(hit)+p(hit)+p (no hit)+p (no hit)+p (no hit)
probability=4/10×4/10×4/10×4/10×4/10×6/10×6/10×6/10
=0.0022
( I think but I'm not 100% sure)
To obtain an estimate of a parameter of a population, we use confidence intervals.
Confidence intervals:
The larger the sample size, the closest the parameter estimate is to the value of the population, as the margin of error of confidence intervals is inversely proportional to the sample size, that is, a greater sample leads to a smaller margin of error.
Thus, you should select the highest sample size in the options.
For more on confidence interval/margin of error, you can check brainly.com/question/22718960
It should be eight if I remember correctly