An astronaut drops a rock into a crater on the moon the distance d(t), in meters, the rock travels after t seconds can be modeled by the function d(t)= .8t^2.what is the average speed in meters per second of the rock between five and 10 seconds after it was dropped

Given: ae ≅ ce ; de ≅ be prove: abcd is a parallelogram. we have that ab || dc. by a similar argument used to prove that △aeb ≅ △ced, we can show that △ ≅ △ceb by. so, ∠cad ≅ ∠ by cpctc. therefore, ad || bc by the converse of the theorem. since both pair of opposite sides are parallel, quadrilateral abcd is a parallelogram.