Divide a parallelogram into two trapezoids, in which () is always equal A. Area B. top and bottom and C. perimeter D. height

After a parallelogram is arbitrarily divided into two trapezoids, the height of the two trapezoids is equal to the height of the original parallelogram. Because the parallelogram has innumerable heights and they are all equal, the heights of the two trapezoids are equal

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1. Xiao Hong uses 64 go pieces to form a regular hexagon on the go board. The number of pieces on each side is equal, and there are pieces at four vertices. How many pieces are placed on each side? Sorry, I made a mistake. It's a square Write the formula according to the standard of grade 4
2. As shown in figure (1), stack the right angle vertex C of two right angle trigonometric rulers together, (1) If ∠ DCE = 35 °, ACB=______ If ∠ ACB = 140 °, then ∠ DCE=______ (2) guess the special relationship between ∠ ACB and ∠ DCE, and explain the reason; (3) as shown in figure (2), if the apex a of 60 ° acute angle of two same right angle trigonometric ruler coincides, then what is the relationship between ∠ DAB and ∠ CAE, please explain the reason
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