What is the average discount for the parts made by Manufacturer#5?
DIVIDE(SUM(l_discount), COUNT(l_partkey)) where p_mfgr = 'Manufacturer#5';
SELECT AVG(T3.l_discount) FROM part AS T1 INNER JOIN partsupp AS T2 ON T1.p_partkey = T2.ps_partkey INNER JOIN lineitem AS T3 ON T2.ps_suppkey = T3.l_suppkey WHERE T1.p_mfgr = 'Manufacturer#5'