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Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

Which of the following is the major negative aspect of crossover designs for research studies? a. prohibitive cost b. residual effects c-subject drepout d. incomplete randomization e. large sample size required

If 0° ≤ θ ≤ 90° and cosθ = 11 15 , what is the value of sin (90° - θ)? a) 11 /15 b) 15/ 11 c) 15 /4 d) 4/15