Properly drawn hidden lines should have dashes drawn with a length of $q,,$ with spaces of $q,$ between the dashes.

a$.0\mathrm{.}6mm$;$0\mathrm{.}3mm$

b$.\mathrm{.}125$ inch, $\mathrm{.}03$ inch

c$.125$ inch, $\mathrm{.}06$ inch

d$.0\mathrm{.}6$ inch, $0\mathrm{.}3$ inch