If the volumes of two triangular prisms are the same the prisms are congruent

I think the correct answer would be false. Having volumes of two triangular prisms being the same does not mean that they are congruent. You can only say that shapes are congruent when you can slide, flip or turn one so that it would fit exactly to the other shape. The can be congruent when the side length and the measurement of the angles in the shapes are the same or equal. Having equal volumes does not necessarily mean they have the same measurement of their angles and side lengths. They could have different slant heights and the areas of their bases.