Answer:True
Explanation: The mechanical waves need a medium through which to transport energy because the perturbation travels inside of the medium so it needs molecules that connect elastically the displacement of the wave. For example the sound mainly uses the air molecules to transport the energy also the sound can be traveled in solid materials like metal rods.
Development of the Embryo. The next stage in development is the embryo, which develops within the amniotic sac, under the lining of the uterus on one side. This stage is characterized by the formation of most internal organs and external body structures.
number 2 because the curve demstrates the crest GOOD LUCK i hope i got you the correct answer if not sorry