Answer:
Autotrophs, unicellular
Explanation:
Algae are simple plant-like protists. They live in seawater, freshwater and in damp places. The algae have chlorophyll meaning they carry out photosynthesis. Some are unicellular and others are multicellular. They have a cellulose cell wall and reproduce either sexually or asexually.
Still waters allow for sediments to settle down on fossils without disturbance. This gives the minerals in the sediments time to perfuse in the fossils and petrify the fossil. The sediments also settle on the fossils without disturbance, take the form of the fossil and get cemented forming molds.
c, 22,800 (4 half lifes, 1/2, 1/4, 1/8, 1/16)