1) they have similar chemical properties.
for example fluorine from the 17th column is a non metal so does all the elements of that group.
2)they have same valence electrons in their outermost shell
example
electronic configuration of
hydrogen 1, lithium 2,1, sodium 2,8,1 and so on.
3) have same valency.
Answer:
Renewable Energy Resources.
Explanation:
Unlike fossil fuels which cannot be recovered when destroyed, these sources of energy can be recovered by a means of recycling . Recycling here reduces solid wastes which is one of the causes of land pollution.
Hydroelectric schemes can only be built in mountain regions where rainfall and rivers are plentiful which involves upset of aquatic ecosystem. This poses a dangerous pollution problem though.
Wind generators and solar panels are not very efficient energy producers. However, future schemes for producing solar energy via solar satellites are promising.
Answer:
The lynx's principal food source is the snowshoe hare. These two species' population cycles are intertwined. When hares are abundant, lynx consume almost nothing else and kill two hares every three days. When hares are sparse, lynx eat mice, voles, squirrels, grouse, ptarmigan, and carrion.
Answer:
B
Explanation:
because they are moving at the same direction
Answer:
Animals needs oxygen's to survive and plants need carbon dioxide to survive. The ozone layer reflects harmful UV rays from the sun to protect the things living on Earth.
