Table:
text: Jesuit Church, Mannheim
Bells
Bells
Year_ Foundry Diameter_mm Weight_kg Nominal_Tone
1956 F. W. Schilling 2023 4 935 g°
1956 F. W. Schilling 1671 2 772 b°
1956 F. W. Schilling 1477 1 921 c′
1754 J. M. Steiger 1275 1 400 es′
1956 F. W. Schilling 1094 857 f′
1956 F. W. Schilling 1006 700 g′
1975 Heidelberger Glockengießerei 892 511 b′
1975 Heidelberger Glockengießerei 790 362 c″

Question: What is the sum of all years with a bell weighing 857 kilograms in the Jesuit Church in Mannheim?