A particular automatic sprinkler system has two different types of activation devices for each sprinkler head. One type has a reliability of 0.89; that is, the probability that it will activate the sprinkler when it should is 0.89. The other type, which operates independently of the first type, has a reliability of 0.79. If either device is triggered, the sprinkler will activate. Suppose a fire starts near a sprinkler head. What is the probability that the sprinkler head will be activated