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.
Explanation:
Methods of Solid Waste Disposal and Management:
Solid Waste Open Burning.
Sea dumping process.
Solid wastes sanitary landfills.
Incineration method.
Composting process.
Disposal by Ploughing into the fields.
Disposal by hog feeding.
Salvaging procedure.
The correct answer is D. Accessory fruit
Explanation.
Fruits are structures that develop from the fertilized ovary of plants and that contain the seed of it, this includes simple, aggregate and multiple fruits. However, there is one type of fruits that do not develop from ovary but from other tissues that are usually near the ovary, these fruits are called accessory or pseudo fruits as they do not fit completely the definition of regular fruits, this includes fruits such as strawberries or pineapples that develop from tissues different to the ovary.
Answer:
Underground mining has lower rates of fatal and nonfatal injuries than surface mining.
Their skin is thin so they're prone to drying out and they cannot hold moisture in their bodies(Waterproof skin)
