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Answer:

This part of the extended information mainly examines the knowledge points of mixed operation:

operation sequence

When calculating at the same level, it is calculated from left to right in turn.

Two-stage operation, first multiply and then divide, then add and subtract.

When there are brackets, count the inside of brackets first, and then count the outside of brackets;

When there are multiple brackets, count the brackets first, then the brackets inside, then the braces inside, and finally the brackets outside.

If there is a power, calculate the power first.

When performing mixed operations, the numbers in parentheses are calculated first, and the parentheses are from small to large. If there is a power, calculate the power first, and then from high to low.