What is the total number of tweets sent by male users on Mondays?
male user refers to Gender = 'Male; 'Monday' is the Weekday; total number of tweet refers to Count (TweetID)
SELECT COUNT(DISTINCT T1.TweetID) FROM twitter AS T1 INNER JOIN user AS T2 ON T1.UserID = T2.UserID WHERE T2.Gender = 'Male' AND T1.Weekday = 'Monday'