A refrigerator test includes multiple measurements. The time it takes to reach 37 degrees in an environment of 60 degrees, door gasket seals integrity, and water pressure after the filter. In a sample of 200 refrigerators tested within 20 days. 10 refrigerators tested each day to make a daily sample. All these measurements recorded in refrigerator file. Download refrigerator file. The manufacturing process changed after day 10, so the samples are marked as phase 1 (before the change) and phase 2 (after the change).

Did the change of process improved the cooling time required to change the internal temperature from 60 to 37?

Group of answer choices

The average time decreased in phase 2 and the variability of the measurement also decreased.

The average time increased in phase 2 and the variability of measurement increased.

The average time decreased in phase 2 but the variability of measurement increased.

The average time increased in phase 2 but the variability of measurement decreased.

Use refrigerator test data. Is the process of temperature change in control?

Group of answer choices

Average measurement is in control but range is not in control

Average measurement is not in control but range is in control

Both average and range measurements are out of control

Both average and range measurement are in control