To estimate the number of eagles living in a region, 7 were…

To estimate the number of eagles living in a region, 7 were tagged.  Later, 18 eagles are observed.  Of these, 4 had been tagged.  Based on these figures, estimate the population of the eagles in the region.  Round your final answer to the nearest eagle.    

An airline stores ticket sales in a sales table with columns…

An airline stores ticket sales in a sales table with columns flight_number and amount. The finance team wants to know the total revenue per flight. Which SQL should they use? SELECT flight_number, SUM(amount) FROM sales GROUP BY flight_number SELECT SUM(amount) FROM sales SELECT flight_number, amount FROM sales ORDER BY flight_number SELECT flight_number, COUNT(amount) FROM sales GROUP BY flight_number Answer: SELECT flight_number, SUM(amount) FROM sales GROUP BY flight_number Explanation: SUM(amount) calculates total revenue per flight, grouped by flight_number. A plain SUM would only give overall revenue. Ordering by flight number doesn’t summarize. Using COUNT(amount) would return the number of sales, not revenue.