Final answer:
After a 10% increase, an additional 6 fish were added to the original population of 60 fish in the lake, making option A the correct answer.
Step-by-step explanation:
The student has asked how many fish were added to the population after a growth of 10%. Given that the normal population of the lake is 60 fish, we can calculate the number of fish added by applying a 10% increase.
To find 10% of the original population, we multiply 60 fish by 0.10 (which is the decimal equivalent of 10%).
60 fish * 0.10 = 6 fish
Therefore, an additional 6 fish were added to the population within the month.
This answer aligns with option a) 6 fish, which is the correct choice.