instruction:
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.
question:
['B', 'K', '9399', 't', '5541', 'w', '1939', '7841', 'q']
answer:
24720


question:
['1709', 'S', 'w', '7725', 'Z', '7755', '8081', '897', 'N', '4449', 'F', 'F', 'M', 'y', 'B', 'h', 's', 'l', 's', '415']
answer:
31031


question:
['R', 'C', '8975', '1419', '7509', '1503', 'T', '315', '1787', 'i', 'R', '1173', 'W', '4101', '217', '4977', 'k']
answer:

31976