Check pls.
5.4 x 10^-2 by 2.5 x 10^-3 by 7.9 x10^-3 m
volume = 107.44 x 10^-8 m^3
Hmmm. I get 106.65 x 10^-8
But, you want that in scientific notation, so it is written as
1.0665 x 10^-6
And, considering the number of significant figures, it would probably be better as
1.1 x 10^-6