Answer:
a
The point estimate of the population mean is 
b
The 80% confidence level is 
c
There is 80% confidence that the true population mean lies within the confidence interval.
Step-by-step explanation:
From the question we are told that
The sample size is n = 18
The standard deviation is 
The sample mean is 
Generally the point estimate of the population mean is equivalent to the sample mean whose value is 
Given that the confidence interval is 80% then the level of significance is mathematically represented as



Next we obtain the critical value of
from the normal distribution table
The value is 
Generally the margin of error is mathematically evaluated as

=> 
=> 
Generally the 80% confidence interval is mathematically represented as

=> 
=> 
The interpretation is that there is 80% confidence that the true population mean lies within the limit
Answer:
8,000 I'm pretty sure so yw if it's right
Okay, so if it leaks out a pint every hour, and a gallon is 8 pints, it will take 8 hours to leak out 1 gallon. Since there are 24 hours in a day, it would leak out 3 gallons every day. Now, assuming the month we are talking about is 31 days, then we multiply 31 with 3, giving us 93 gallons in a month.
Do you need help with the third too?
Answer:
x= -18
Step-by-step explanation:
Make an equation
x/-2=9
Multiply both sides by -2 to isolate the variable
-2(x/-2)=(9)-2
x= -18
Hope this helps! :)