Answer:
Ever since the existence of life of humans on Earth, the humans have been making progress to understand themselves and the mother nature.
In the start, the humans were hunter- gatherers. Hunter- gatherers can be described as humans which use wild life plants and animals for food. The humans used to live in jungles and eat the wild- life plants and animals. They used leaves from the trees to cover their bodies. Heat was produced by rubbing the rocks.
After this time, the humans learned the techniques of cultivating plants for food. They started cultivating crops and depend on them for living. During this time, humans learned the art of farming and agriculture. But they couldn't understand the effects of various pathogens infecting the crops and humans at that time.
After this time, humans learned the art of preserving foods in different forms like pickles etc. They also learned that certain types of plants could be used to treat wounds and other diseases.
With the passage of time, people learned to make and use machinery for making their tasks easier. The usage of machinery progressed rapidly and the industrial revolution began. People became more diverted to this sector rather than farming. They started to move towards the cities to find better jobs in industries.
Life after industrial revolution was much easier as humans had made a lot of equipments which aid them to have a better life style. Science has been developing since that time day by day.
Explanation:
Answer:
Sky Cover. The total amount of clouds in tenth. Plotted in the station circle according the ... The wind speed is plotted as feathers and half-feathers representing 10 and 5 knots, ... For values above 10 miles, the values are omitted from the map.
Explanation:
The electrons in the outermost shell of the covalent compounds are shared by nearby atoms. As there are no free electrons for conducting electricity, the covalent compounds are perfect insulators at absolute zero. As the temperature increases, some electrons move from valence band to conduction band. This gives rise to conductivity. But as the numbers of charge carriers are very low, covalent compounds are poor conductors. On the other hand metals are good conductors cause of their bonding. Metallic bonding consists of a sea of electrons rather than discreet bonds. The free electrons are able to move freely. Since electricity and heat need electrons to move, the bonding promotes conductivity.
