helpp, please!

Andre wanted to measure the width of a creek by his camp but cannot get to the other side of the creek. Andre decided to construct two triangles to determine the width of the creek indirectly. Sighting the position of a tree on the opposite bank of the creek and placing 4 wooden pegs at point N, O, P, and Qas shown in the figure such that MN is perpendicular to NP, NP is perpendicular to PQ, and O is the midpoint of NP. Andre claims that AMNO and AQPO are congruent.

Part A: Provide a valid argument, using geometry theorems or postulates, to validate Andre's claim that AMNO and APQO are congruent.

Part B: Which segment should Andre measure to determine the width of the creek? Explain why.

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