A telecоm cоmpаny hаs а calls table with cоlumns region and call_duration. Analysts want to find regions where the average call duration is less than 3 minutes. Which query is correct? SELECT region, AVG(call_duration) FROM calls GROUP BY region HAVING AVG(call_duration) < 3 SELECT region, AVG(call_duration) FROM calls WHERE AVG(call_duration) < 3 GROUP BY region SELECT region, call_duration FROM calls GROUP BY region HAVING call_duration < 3 SELECT region, SUM(call_duration) FROM calls GROUP BY region HAVING SUM(call_duration) < 3 Answer: SELECT region, AVG(call_duration) FROM calls GROUP BY region HAVING AVG(call_duration) < 3 Explanation: HAVING is the correct clause for filtering by an aggregate. AVG(call_duration) gives the mean per region. Using WHERE with an aggregate is invalid. Checking SUM(call_duration) < 3 is meaningless for durations, and filtering on row-level call durations is not correct.
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