A factory manufactures nails and screws. The profit yield is $$2$ per kg nails and $$3$ per $kg$ screws. Three units of labour are required to manufacture $1kg$ nails and $6$ units to make $1kg$ screws. Twenty$-$four units of labour are available. Two units of raw material are needed to make $1kg$ nails and $1$ unit for $1kg$ screws. Determine the manufacturing policy that yields maximum profit from $10$ units of raw material.