You can refer to How Carbon-14 Dating Works, from How Stuff Works, to help you answer the question.
You can continue to fill the funnels as different classes arrive.
Empty the graduated cylinders between classes if the volume is more than about 25 ml.
There were no eyewitnesses, but there are several suspects. You need to determine the exact time at which Frosty was put into the funnels to melt away, leaving no trace.
On a separate sheet of paper, immediately record the volume of Frosty's melted remains (water) in your graduated cylinder and note the time on the clock.
They should also understand that the atoms of any element are alike but are different from atoms of other elements.