Answer:
○ b.

Explanation:
This is what is called the Midsegment Theorem, which states that the relation of a triangle's midpunkt is parallel to the triangle's third side, and the mid-segment length is half the third side length, so you would double 35 to arrive at your answer:
![70 = [2][35]](https://img.qammunity.org/2020/formulas/mathematics/middle-school/v64l0ux8okdgdp472me476y0g0nu775063.png)
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