Physical Sciences
The U.S. Geological Survey collects water-level measurement data from various locations. Data from the La Pine Basin, Oregon, are being used to study changes in the water table. Twelve days were randomly selected, and the water table in feet below land surface on each day is given in the following table
|
12.30
|
12.29
|
12.30
|
12.35
|
12.37
|
12.40
|
|
12.38
|
12.37
|
12.38
|
12.42
|
12.46
|
12.52
|
Is there any evidence to suggest the mean water table is less than 12.4 feet? Assume the underlying distribution is normal, σ = 0.07 and use a = 0.025.