Anela is a computer scientist who is formulating a large and complicated program for a type of data processing. She has three ways of storing and retrieving data: cloud storage, disk, or hard drive. As an experiment, she sets up her program in three different ways: one using cloud storage, one using disks, and the other using a hard drive. Then she makes four test runs of this type of data processing on each program. The time required to execute each program is shown in the following table (in minutes). Use a 0.01 level of signi­cance to test the hypothesis that the mean processing time is the same for each method.

Hard Drive Cloud Disks 7.0 8.7 7.2 9.3 9.1 6.4 7.9 7.5 9.8 8.0 7.7 8.2