Because many smart people figured out it was the best order to do things in.
There is no operation for a single number and so there can be no order of operation.
There are 6 pats in an operation order
order of operation
33.8
Operation Brevity order of battle happened in 1941.
Operation Chahar order of battle happened in 1937.
Order of battle Swatow Operation happened in 1939.
They must follow the order of operation because if they don't, they will not get the same answer.
operation order
operation order
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