Final answer:
To determine the sum of the amount changes in bacteria after the 7th day, we need to refer to the given data table. However, the table is not provided in the question, so we cannot accurately calculate the sum.
Step-by-step explanation:
To determine the sum of the amount changes in bacteria after the 7th day, we need to refer to the given data table. However, the table is not provided in the question, so we cannot accurately calculate the sum. Please provide the data table so I can assist you further.