Well, you *should* be able to do it using the CONVERT function and some math,
but it comes up with an incorrect answer.
=CONVERT((CONVERT(A1,"gal","l")*1000)^(1/3),"cm","ft")^3
The error is in the very first conversion. The problem is that the CONVERT
function does not seem to properly convert gallons to liters (nor does it
properly convert quarts to liters (unless MS is using a different standard).
Of course, the error introduced is small, resulting in an Excel derived
conversion factor of 0.133709643 rather than the 0.133680556 that seems to be
correct.
--ron