Respuesta :
-- No.
Neither a trapezoid nor a parallelogram need be a rhombus,
and a trapezoid can never be.
-- No.
Both pairs of opposite sides of a parallelogram are congruent,
but a trapezoid need not have any two of its sides congruent.
-- No.
Any two adjacent angles of a parallelogram are supplementary,
but no two angles of a trapezoid need to be supplementary.
-- Yes.
Both pairs of opposite sides of a parallelogram are parallel,
and one pair of opposite sides of a trapezoid (the 'bases')
are parallel.
A trapezoid is a quadrilateral with two opposite sides parallel. A parallelogram fulfills that requirement but also has the other two sides parallel. So a trapezoid can be a parallelogram or, to put it the other way, a parallelogram is a special case of a trapezoid. This (from Wikipedia) is the definitive diagram.