Which of the following equations would result in destructive interference with the wave y equals negative 2 sine left parenthesis Start Fraction 2 pi over 3 End Fraction x right parenthesis?

Which statement is not always true for a parallelogram? (a) opposite sides are congruent. (b) diagonals bisect each other. (c) it has 4 congruent angles. (d) consecutive angles are supplementary.

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A20? -foot ladder is placed against a vertical wall of a? building, with the bottom of the ladder standing on level ground 19 feet from the base of the building. how high up the wall does the ladder? reach?