Answer:
Air, water life without these is nothing
The correct terms to fill in the blanks are gastric cavity and extracellular. In cnidarians, the mouth of both the medusa and polyp form opens into an internal gastric cavity where extracellular digestion takes place. The polyp and medusa are body forms that can be found in the phylum Cnidaria. The polyp is a nonmotile body form while the medusa is a free swimming body form.
Dont Listen to me but i (Think) it's Nitrogen
In alpha decay, the nucleus loses two protons. In beta decay, the nucleus either loses a proton or gains a proton. In gamma decay, no change in proton number occurs, so the atom does not become a different element. ... If it loses two protons through alpha decay, it will have 82 protons
D. Electromagnetic waves
<span><span> Generally, Electromagnetic waves consist of both electric and magnetic field waves. These waves oscillate in perpendicular planes with respect to each other, and are in phase.</span><span>The creation of all electromagnetic waves usually begins with a charged particle, which creates oscillating electric and magnetic fields.</span><span>Once they are in motion, the electric and magnetic fields that are charged in particles creates are self-perpetuating: time-dependent change in one field (electric or magnetic) to produce the other.</span></span>