A wildlife project records unusual bird calls at several remote sites. Each day is classified as either quiet or active. The probability of an active day is . Day classifications are independent across days, and all sites share the same classification on a given day.
Conditional on a quiet day, the number of calls recorded at each site follows . Conditional on an active day, it follows . Given the day's classification, the counts at different sites are independent. Counts on different days are independent.
Let be the number of calls at one specified site on a randomly selected day.
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