The crust is the outside layer and also the thinnest.
To solve this problem, we can simply calculate for the
dose by multiplying the volume of solution containing Selenium 75 and the
activity of the Selenium 75. That is:
dose = 4.1 mL * (45 μCi/mL)
dose = 184.5 μCi
Matematically speaking, maybe because:
The number of substances = number of elements + number of different combinations of those elements
The correct answer is C. Colligative properties only depend upon the number of solute particles in a solution but not on the identity or nature of the solute and solvent particles. I hope this anwers your question.