List all captains who were captains of shipments that carried rice

List all captains who were captains of ships that carried rice. The captain may not necessarily been the captain of the shipment that carried the rice

For each origin, display the origin as well as the number of unique captains who have been captains of shipments which left that port.

shipment SHIPMENT SHIP-NO ID shi ship_no ship_class capacity purch_date manufacturer_id captain capt_id ID SHIPMENT_DATE ORIGIN DESTINATION 0O cense_grade fname 0O name VAL_DATE 0 shipment_line -SHIPMENT-ID manufacturer distance ORIGIN anufacturer_ID Name 0O M NO -DESTINATION UANTITY MILES DAYS ate ep Id Bid Preference item item_no item_type escription weight