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Chrism is the oil used by the bishop during the Sacrament of Confirmation.
Water is used by the minister (bishop, priest, deacon) at Baptism. Chrism is one of the oils used at Baptism, the other being the oil of the Catechuminate.
Water is used in the WATER cycle, because its the WATER cycle. Without water vegetation and animals would die out. Leading to the end of the world for humans.
Water can be used for various purposes. Some examples are:
Drinking (All life as we know it needs water to survive) Hydroelectricity Putting out fires Pools, lakes, oceans, and recreation Washing...