Calculate parasite drag coefficient from drag polar
Well, $C_D = C_{D,0} + k_1 C_L^2 + k_2 C_L$ according to Brandt et al's "Introduction to Aeronautics: A Design Perspective," so the parasite drag coefficient is $C_{D,0}$ or 0.038.

(Also, $k_1 = 0.0458$ and $k_2 = 0$.)