Answer:Ice melts when heat energy causes the molecules to move faster, breaking the hydrogen bonds between molecules to form liquid water. In the melting process, the water molecules actually absorb energy.
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:
parallel and intersect at right angles
Explanation:
The roads in the urban areas tend to be very well organized and constructed. They tend to be parallel to each other, and also to intersect at right angels. The reason for this kind of building of the roads in the urban areas is to make the movement in the urban areas much easier and more efficient, mostly putting the accent on the traffic. It is a fact that the traffic is a big problem in the urban areas, so by constructing the roads in a well organized manner, the traffic jam eases up and the citizens can move more easily and quickly.
el carbon es bueno para el atmosphere
They are inversely related. As the distance increases the magnetic attraction decreases and when the distance decreases the magnetic attraction increases
