What is the sum of the first four terms of sequence S?
(1) After the first two terms of S, the value of each term of S is equal to the average (arithmetic mean) of the last two preceding terms.
(2) The average (arithmetic mean) of the first three terms of S is 10.
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AStatement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
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BStatement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
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CBOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
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DEACH statement ALONE is sufficient.
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EStatements (1) and (2) TOGETHER are NOT sufficient.