Please list the opening time on Mondays of all the Yelp_Businesses in Anthem that are still running.
Mondays refers to day_of_week = 'Monday'; in Anthem refers to city = 'Anthem'; are still running refers to active = 'true'
SELECT T1.opening_time FROM Business_Hours AS T1 INNER JOIN Days AS T2 ON T1.day_id = T2.day_id INNER JOIN Business AS T3 ON T1.business_id = T3.business_id WHERE T2.day_of_week LIKE 'Monday' AND T3.city LIKE 'Anthem' AND T3.active LIKE 'True' GROUP BY T1.opening_time