Given a table below which gives the years in A.D. for an archaeological excavation site using the method of tree ring dating:

Part A:
The sample mean is given by:

Therefore, the sample mean is 1268.
Part B:
We calculate the sample standard deviation as follows:

Part C:
The 90% confidence interval is given by:
If you are talking about finding the slope of BC then it looks like you have to find the square root of 3 which is approx 1.7 then find the slope.
slope equation is rise over run (or y over x): y1 + y2 divided by x1 + x2.
From this you should be able to find the answer
There are 3 feet in a yard
so how many times can 3 go into 41 (13 times)
3 x 13 = 39
41 -39 = 2
13 2/3
Hope this helped!
The ratio is 1:5 tbh or that’s what I think ahahahah