If the rectangular wooden frame nailed by four pieces of wood is deformed into the shape of parallelogram ABCD and its area is half of the rectangular area, then the minimum inner angle of the parallelogram is () A. 30B. 45C. 60D. 90

The rectangular wooden frame nailed by four wooden strips is transformed into the shape of parallelogram ABCD, and its area is half of the rectangle area. The parallelogram ABCD is changed from the original rectangle, ∵ FG = BC, FH = 2ae. Also ∵ HF = AB, ∵ AB = 2ae. In RT △ Abe, ab = 2ae, ∵ B = 30 °. So a

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