Question: What is the average discount for the parts made by Manufacturer#5?
SQL: 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'