The presence of photosynthesizing algae.
Answer:
Stereoscope
Explanation:
Stereo Microscopes enable 3D viewing of specimens visible to the naked eye.
Answer:
2 electrons
Explanation:
According to the octet rule, atoms must bond to each other, sharing electrons among themselves in an attempt to complete their valence shell (last layer of the electrosphere). In other words, an atom becomes stable when it has 8 electrons in its valence shell.
Oxygen atoms have six electrons in their valence shell, so to achieve the stability suggested by the octet rule (eight electrons), these atoms share two electrons, forming one oxygen gas (O₂) molecule.
