Answer:
Their skeletal structure and possibly how they look but usually not. You can also look at the way they live and the biomes they live in.
Explanation:
The Precambrian era envelopes the major bulk of the history of the Earth, beginning from the creation of the planet approx 4.5 billion years ago and terminating with the origination of composite, multicelled forms of life approximately 4 billion years after.
The Precambrian refers to the earliest of the geologic ages that are signified by the distinct layers of sedimentary rock. The Earth was about more than six hundred million years old when life started. The planet had cooled down from its native molten state, creating a solid crust and oceans formed by water vapor in the atmosphere.
At about three billion years ago, the atmosphere of the Earth was virtually devoid of oxygen. At approximately 2.4 billion years ago, oxygen was discharged from the seas as a waste product of photosynthesis by cyanobacteria. The levels of the gas slowly raised, attaining about 1 percent around two billion years ago.
Approximately 800 million years ago, the levels of oxygen attained about 21 percent and started to breathe life into more composite species. The oxygen-rich ozone layer was also created, protecting the surface of the Earth from the harmful solar radiation.
Answer:The mass of a liquid can be measured using one of these two methods: Method n 1: - Measure the mass of the empty container. - Pour the liquid into the container and measure the new mass. - The mass of liquid is obtained by subtracting the mass of the container to the total mass. hope this makes sense :)
Explanation:
The answer is A "the first four steps of meiosis" because in mitosis the first stage is Prophase in which the chromsomes condense and centrioles move to opposite poles. And in Meiosis, the first stage is Prophase I in which the same thing occurs
