[Tom]

When one lone pair of electrons and four bonding pairs of electrons are around a central atom, the lone pair will occupy?
      
An axial position, an equatorial position, or either an axial or equitorial position (no preference) or lastly either an axial or equitorial position depending on the central atom.

[Donaldson Tan]

Equatorial. To minimise intra-molecular electronic repulsion.