For average speed, we divide the total distance covered by the total time taken.
After doing that, you will see that Jane has the lowest average speed.
I believe the answer is compound B may have a lower molecular weight compared to compound A.
At the same temperature, lighter particles of a compound have a higher average speeds than do heavier particles of another compound. Thus, particles of compound B are lighter than those of compound A and thus they have a higher average speed, hence evaporating faster compared to compound A.
When you immerse an ionic compound<span> in </span>water<span>, the ions are attracted to the </span>water <span>molecules, each of which carries a polar charge. If the attraction between the ions and the </span>water <span>molecules </span>is<span> great enough to break the bonds holding the ions together, the compound </span>dissolves<span>. </span>
