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Explanation:</h2><h2>
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Because we perform something like common factor, so this guarantee that corresponding digits have regarding coefficients have the same place value. Remember that a number written in scientific notation is given by the product of a number between 1 and 10 and another number that is power of 10. For example, let's write two examples about this:
Addition:

Addition:

Subtraction:

The answer is C. i know because i looked it up
Answer:
pic1=56-28x
pic2=3cd+12c
pic3=s−t
pic4= the last answer
pic5= the third answer
Step-by-step explanation:
i did the math so just trust me