Solution:
(c) The combination of sodium hydroxide and ammonium hydroxide with copper salt produces a pale blue-colored precipitate, whereas the reaction with ferrous salt solution produces a dirty green-colored precipitate.
d) As a result of their reaction with Fe(II) salt, sodium hydroxide and ammonium hydroxide produce a filthy green coloured precipitate, but their reaction with Fe(III) salt solution produces a reddish brown insoluble precipitate.