Picture?? This question is incomplete just get a picture then I can answer it
Answer:
square
Step-by-step explanation:
The opposite angles are congruent, the diagonals bisect each other, the opposite sides are parallel, the diagonals bisect the angles
Im assuming the height is dropped so that it is the halfway point. this would then make the base 5cm, with a height of 12cm. if that is the case then the answer should be 13
The last statement is true
1. Suppose that BC is hypotenuse, then by Pythagorean theorem:

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2. If BC is not hypotenuse, then BC is a leg and AC is hypotenuse (because AC>AB). Hence by Pythagorean theorem:

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