Question: how to make dntp mix 10mm?
Answer: 1 microliter 100 mM dATP.
1 microliter 100 mM dGTP.
1 microliter 100 mM dCTP.
1 microliter 100 mM dTTP.
36 microliter H2O.
Because, now you have 400 mM dissolved in 40 microliter total volume, 400 mM/40 = 10 mM dNTP mix.