M [approximately equals] T^{x}.g^{y}.[sigma]^{z}.a^{u},

we have, considering in turn length, time and mass,

y - 3z + u = 0, 2x + 2y = 0, x + z = 1;

so that

y = -x, z = 1 - x, u = 3 - 2x.

Encyclopaedia Britannica, 11th Edition, "Capefigue" to "Carneades" Volume 5, Slice 3 · 第 40 / 74 题