A quality managemet specialist in an organization that promotes preventative rather than corrective quality management practices is given the following mean control chart. The specialist should be most interested in intervention and investigation of the process for which of the following sample $($ s $),$ ?if at all?

chart

Question $10$ ?options:

None. Process in control.

Sample number $7$

Sample number $15$

Sample number $3$

Sample number $12$