The tensile strength of an alloy has double specification limits. If the process average tensile strength is below 800 kg/cm2 or above 1200 kg/cm2, it is desired to accept such lots with a probability of 0.08. For lots with a process average of 1000 kg/cm2, it is desired that the probability of acceptance be 0.96.
The distribution of tensile strength is normal, with a standard deviation of 80 kg/cm2. Find the variable sampling plan and describe its operation.