Final answer:
The sum of 9.98 and 0.065 is 10.045, which is correctly aligned with the decimal points and added as regular numbers. Option 2) is the right answer without the need for rounding off to any specific significant figures as no such instructions were provided in the question.
Step-by-step explanation:
The question asks for the result of adding 9.98 and 0.065. To find the sum, we align the decimals and add:
9.98
+0.065
------
10.045
Therefore, the correct answer is 10.045, which is option 2). Remember, when adding decimals, it is important to align the decimal points and then proceed with the addition as you would with whole numbers, carrying over if necessary. Afterward, you place the decimal in the resulting sum directly below the other decimals.
It is important to note that the explanation provided in the reference regarding significant figures and rounding does not apply to this particular calculation, as the question did not ask for rounding to a specific precision.