There is some evidence that ownership of a dog may have predictive value in determining whether an individual will survive a heart attack. The following data are from a random sample of 95 individuals...

There is some evidence that ownership of a dog may have predictive value in determining whether an individual will survive a heart attack. The following data are from a random sample of 95 individuals who each suffered a severe heart attack. The data classify each of these individuals with respect to (1) whether they were still alive 1 year after their attack and (2) whether they had a dog as a pet.

Do these data prove, at the 5 percent level of significance, that owning a pet and survival are dependent? Explain carefully what null hypothesis you are testing and what test statistic you are using.