B. I think it is b because i feel like a dot plot would be helpful
The three-dimensional figure that will produce a trapezoid if its cross section was cut by a plane that is not parallel to its base is the rectangular pyramid. If a plane was cut parallel to the base of the pyramid, the shape that would be produced would be a rectangle.
Step-by-step explanation:

Answer: (2α) = cos²(α) - sin²(α)
Step-by-step explanation:
The expression for cosine of the sum of two angles is:
cos (α + β) = cos(α)*cos(β) - sin(α)*sin(β)
in case α = β
cos ( α + α ) = cos (2α) = cos(α)*cos(α) - sin(α)*cos(α)
Hence cos (2α) = cos²(α) - sin²(α)