Geometry

Question Analysis
This question involves calculating the measures of angles in a parallelogram.
The main focus is on understanding the angle properties of parallelograms, specifically the fact that opposite angles are equal and adjacent angles are supplementary.

Key Concept Explanation
In any parallelogram:
Opposite angles are congruent
Adjacent angles are supplementary

Step-by-Step Solution
Given ∠A = 70°.
Since ∠A and ∠C are adjacent angles in a parallelogram, they must be supplementary.
→ ∠A + ∠C = 180° → 70° + ∠C = 180° → ∠C = 110°

Common Mistakes
Mixing up adjacent and opposite angles
Assuming all angles are 90°, which is only true in rectangles and squares
Forgetting basic properties of parallelograms such as adjacent angles are supplementary

Summary
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