Kevin claims he can draw a trapezoid with three right angles. Is this possible?
Obviously, Kevin draw a rectangle.
Is a rectangle a particular type of trapezoid?
It depends on a definition of a trapezoid. Traditionally, yes. So, Kevin can do it.
If a trapezoid is defined as a polygon with four sides (that is, quadrilateral) and two sides of it are parallel to each other, than a rectangle can be considered as a type of trapezoid.
In this case all theorems proven for a trapezoid are true for rectangles.
The above definition is the one traditionally agreed upon.
By the way, in this case, a parallelogram is also a particular type of a trapezoid.
If, however, the definition states that two sides of a quadrilateral must be parallel and two other must not (notice, this is not a typical definition), then rectangle is not a particular type of trapezoid and Kevin could not draw a trapezoid with three right angles.