Final answer:
To calculate the average atomic mass, information on the isotopes' masses and abundances is necessary, which is not provided here. Therefore, a correct answer cannot be given for Michelle's sample.
Step-by-step explanation:
To determine the average atomic mass of Michelle's sample, we would need information on the abundance and atomic masses of the isotopes present in her sample. Since the provided information does not include the necessary details about the isotopes, we cannot accurately calculate the average atomic mass of her sample. Typically, the calculation would involve multiplying the mass of each isotope by its relative abundance and then summing these values to get the average atomic mass.
The general formula to calculate average atomic mass (A) looks like this:
A = ∑(mass of isotope × fractional abundance)
However, without specific details on the isotopes' masses and their abundances, we would only be guessing from the options a), b), c), and d). As such, it's not possible to provide an accurate response to this question.