Identify the mistake(s) in each flowchart segment.

a. Figure a - the sort symbol should be a manual operation symbol.
b. Figure b - the file update symbol should be a computer operation symbol, and the arrow from transaction file should flow into file update.
c. Figure c - the arrows should point from left to right and a computer operation symbol is needed between the source data and the master file symbols.
d. Figure d - the symbol for Endorsed should be a manual operation symbol, and endorsed checks are sent to the bank, so the file symbol should be replaced with a terminal symbol.