Using the method of difference of two cubes,

\(a^{3} - b^{3} = (a - b)(a^{2} + ab + b^{2})\)

\((0.03)^{3} - (0.02)^{3} = (0.03 - 0.02)((0.03)^{2} + (0.03)(0.02) + (0.02)^{2}\)

= \((0.01)(0.0009 + 0.0006 + 0.0004)\)

= \(0.01 \times 0.0019\)

= \(0.000019\)