The mortality experience of 8146 male employees of a research, engineering, and metal fabrication plant in Tonawanda, NY was studied from 1946 to 1981. Potential workplace exposures included welding fumes, cutting oils, asbestos, organic solvents, and environmental ionizing radiation, as a result of waste disposal during the Manhattan Project of WWII. Comparisons were made for specific causes of death between mortality rates in workers and US white male mortality rates from 1950 to 1978. Suppose that 17 deaths from cirrhosis of the liver were observed among workers who were hired prior to 1946 and who had worked in the plant from 10 or more years, whereas 6.3 were expected based on the US white male mortality rate.

Perform a significance test to assess whether there is an association between mortality from cirrhosis of the liver and duration of employment in the group hired after 1945. Report a p-value.