What is the average amount of money spent by a customer in Italy on a single film rental?
Italy refers to country = 'Italy'; average amount = divide(sum(amount), count(customer_id)) where country = 'Italy'
SELECT AVG(T5.amount) FROM address AS T1 INNER JOIN city AS T2 ON T1.city_id = T2.city_id INNER JOIN country AS T3 ON T2.country_id = T3.country_id INNER JOIN customer AS T4 ON T1.address_id = T4.address_id INNER JOIN payment AS T5 ON T4.customer_id = T5.customer_id WHERE T3.country = 'Italy'