Final answer:
The correct answer to the question is that 55.6% of the sphere's volume is submerged when it floats in glycerin.
Step-by-step explanation:
The student's question is asking which percentage of the sphere's volume is submerged when it floats in glycerin.
According to the question, 70.0% of the sphere's volume is submerged in water, and when the sphere is placed in glycerin, 55.6% of its volume is submerged.
Therefore, the correct answer is that 55.6% of the sphere's volume is submerged in glycerin.