While learning through this gemara, I came up with several questions.

If we learn that indeed all Levee'im were really 10 amot tall, and that there were only 3 1/3 amot between the ground and the bottom of the mizbeach, then we should learn that the minimum height that one is liable for carrying is TWENTY tefachim, not 10 (1 amah = 6 tefachim, so 3 1/3 amot = 20 tefachim). Why is the gemara learning from this case that the minimum height one is liable for carrying is ten tefachim?

Then the gemara gives an alternative answer from the aron, assuming that the levee'im were of average height (3 amot). Since the aron was only ten tefachim high, there was at least two amot of space between the ground and the bottom of the aron, so once again, how do we derive the number ten as being the minimum height one is liable for carrying?

And if the levee'im were of normal height, how could they carry the mizbeach, which was ten amot tall? The gemara says that really only Moshe was ten amot tall, but not everyone else. This brings another question to mind: Did Moshe help with carrying the vessels of the mishkan? With his height, he obviously would have done the mizbeach, but how could he do it alone?