-22, -19, -16, -13, . a =-25(3)' b. a =-25+3 C. a = 3n - 25 d. a = 3n - 16 69. Find the sum of the first 18 terms of the arithmetic sequence, if the...

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68. -22, -19, -16, -13, ...a. a =-25(3)'b. a =-25+3C. a = 3n - 25d. a = 3n - 1669. Find the sum of the first 18 terms of the arithmetic sequence, if the first term is -2 and the common differenis 6.a. 882b. 1764C. 900d. 58815