Which question is undefined? A.-0/2/10 B.(-7-0)/14 C.7/0 D.(4-4)/8

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem

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Will give brainliestbased on the topographic map of mt. st. helens, what is the contour interval if the volcano height is 2,950 m?