Answer: (17.42, 20.78)
Step-by-step explanation:
As per given , we have
Sample size : n= 9
years
Population standard deviation is not given , so it follows t-distribution.
Sample standard deviation : s= 1.5 years
Confidence level : 99% or 0.99
Significance level : 
Degree of freedom : df= 8 (∵df =n-1)
Critical value : 
The 99% confidence interval for the population mean would be :-


Hence, the 99% confidence interval for the population mean is (17.42, 20.78) .
Parallel lines have the same slope.
Answer:
Step-by-step explanation:
Here:
- Solid
- Liquid
- gas
If I remember how to do this right I’m pretty sure you just divid by 178.90 by 5.75 wich gives you 31.11 for the tax rate