Eruvin 14: Rabbinic Geometry Represent!

Parameters needed for a koreh and lechi, and a round koreh, with its circumference and diameter... leads to a tangent... King Solomon's pool that was 10 amot across, and 30 amot in circumference (an approximation of our knowledge of πd, or, if you prefer, 2πr). This Yam shel Shlomo answers a question about the brim of a koreh. And what about the volume? As compared to mikvaot (at 40 seah!). Also, the next mishnah, defining the lechi: 10 tefachim by amount (or 3 tefachim, according to R. Yosi). How does this align with the requirement for one or two lechis? Plus, a definition of "any amount" for the width/depth of the lechi.