Which of the following statements are true? Check all that apply. A properly running process should not have random variations. O A worker sleeping on duty can result in an assignable variation in a process. OIf the R-chart is in control then the 7-chart from the same data is also in control. Olf every sample mean in a process is 24 then the centreline for the ī-chart is also 24. Random or natural variations are present in every production process to some degree. DA non-regular variation in a process that can be identified and eliminated is a random variation. The c-chart can be used to plot the number of defective items in a process. DA sample point below the upper control limit in an R-chart indicates the process is out of control. DA process that has all sample points within the control limits is always in control. O process is not statistically stable if it exhibits a consistent upward trend.