Which statement is true about the polynomial negative 10 m to the 4th power n cubed plus 8 m squared n to the 6th power plus 3 m to the 4th power n cubed minus 2 m squared n to the 6th power minus 6 m squared n to the 6th power after it has been fully simplified?

Combine like terms: the terms with m⁴n³ give −10 + 3 = −7, while the terms with m²n⁶ give 8 − 2 − 6 = 0. The simplified polynomial is −7m⁴n³, which is a monomial. Its degree is 4 + 3 = 7, so the true statement is “It is a monomial with a degree of 7.”

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