Read this: In Ancient Egypt green was the symbol of regeneration and rebirth, and of the crops made possible by the annual flooding of the Nile. For painting on the walls of tombs or on papyrus, Egyptian artists used finely-ground malachite, mined in the west Sinai and the eastern desert- A paintbox with malachite pigment was found inside the tomb of King Tutankhamun. They also used less expensive green earth pigment, or mixed yellow ochre and blue azurite. To dye fabrics green, they first colored them yellow with dye made from saffron and then soaked them in blue dye from the roots of the woad plant.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): How did Egyptians dye fabrics yellow?
saffron