<Li> Sachamama--Means Mother Tree, goddess in the shape of a snake with two heads </Li> <Li> Yakumama--Means mother Water . Represented as a snake . When she came to earth she transformed into a great river (also Illapa). </Li> <P> The Inca Empire employed central planning . The Inca Empire traded with outside regions, although they did not operate a substantial internal market economy . While axe - monies were used along the northern coast, presumably by the provincial mindaláe trading class, most households in the empire lived in a traditional economy in which households were required to pay taxes, usually in the form of the mit'a corvée labor, and military obligations, though barter (or trueque) was present in some areas . In return, the state provided security, food in times of hardship through the supply of emergency resources, agricultural projects (e.g. aqueducts and terraces) to increase productivity and occasional feasts . The economy rested on the material foundations of the vertical archipelago, a system of ecological complementarity in accessing resources and the cultural foundation of ayni, or reciprocal exchange . </P> <P> The Sapa Inca was conceptualized as divine and was effectively head of the state religion . The Willaq Umu (or Chief Priest) was second to the emperor . Local religious traditions continued and in some cases such as the Oracle at Pachacamac on the Peruvian coast, were officially venerated . Following Pachacuti, the Sapa Inca claimed descent from Inti, who placed a high value on imperial blood; by the end of the empire, it was common to incestuously wed brother and sister . He was "son of the sun," and his people the intip churin, or "children of the sun," and both his right to rule and mission to conquer derived from his holy ancestor . The Sapa Inca also presided over ideologically important festivals, notably during the Inti Raymi, or "warriors' cultivation," attended by soldiers, mummified rulers, nobles, clerics and the general population of Cusco beginning on the June solstice and culminating nine days later with the ritual breaking of the earth using a foot plow by the Inca . Moreover, Cusco was considered cosmologically central, loaded as it was with huacas and radiating ceque lines and geographic center of the Four Quarters; Inca Garcilaso de la Vega called it "the navel of the universe". </P>

Who controlled the economy in the incan empire
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