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18: The combined SAT scores in the United States could be approximated by, T(t)=0.0101t3+0.5865t29.6t+1038(09523) ' In the years 1967 1990. Here t is the number of years since 1967, and T is the combined SAT score average for the United States. Find all points of inection of the graph of .T. Round coordinates to 2decimal places if necessary. A) (11.75, 989.90),(26.90, 1007.45) B) (19.33, 998.29) ' C) (23,1004.56) D) (0:0) E) (0,0), (23,100456)