List the active business ID and its stars of the businesses fall under the category of Food.
active business ID refers to active = 'true'; category of Food refers to category_name = 'Food'
SELECT DISTINCT T1.business_id, T1.stars FROM Business AS T1 INNER JOIN Business_Categories AS T2 ON T1.business_id = T2.business_id INNER JOIN Categories AS T3 ON T2.category_id = T3.category_id WHERE T3.category_name = 'Food' AND T1.active = 'true'