Many birds can attain very high speeds when diving. Using radar, scientists measured the altitude of a barn swallow in a vertical dive; it dropped $188$ m in $3\mathrm{.}0$ s$.$ The mass of the swallow was estimated to be $0\mathrm{.}018$ kg and its cross$-$section area as $5\mathrm{.}6\backslash$times $10^4$m$^2$

What was the drag coefficient for this swallow as it dove?