In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.

['B', 'K', '9399', 't', '5541', 'w', '1939', '7841', 'q']
24720

['29', 'N', '5061', '7191', 'z', '8367']
20648

['E', '8271', 'g', 'k', '421', '7493', 'K', 'W', '8367', 's', '1059', 'g', '9103', 'D', '185', 'r', '4779', 'T']

39678