Which episode has segment D on custom motorcycle tanks?
CREATE TABLE table_15187735_20 (episode INTEGER, segment_d VARCHAR)
SELECT MIN(episode) FROM table_15187735_20 WHERE segment_d = "Custom Motorcycle Tanks"
### Context: CREATE TABLE table_15187735_20 (episode INTEGER, segment_d VARCHAR) ### Question: Which episode has segment D on custom motorcycle tanks? ### Answer: SELECT MIN(episode) FROM table_15187735_20 WHERE segment_d = "Custom Motorcycle Tanks"