A quadrilateral has interior angles of 85 degrees, 95 degrees, 100 degrees and one unknown angle. Select all the statements that are true of this quadrilateral.

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Adding 85, 95 and 100 gives 280 degrees, and since the four interior angles must reach 360 degrees the unknown one is 360 minus 280. Starting from 180 degrees applies a three-sided total to a four-sided shape, which would leave a negative amount for the missing angle.