Some dinosaurs had feathers although they could not fly but birds have feathers that help them to fly. In the context of evolution this means that

Both the energy sources coal and pertoleum take millions of years for their formation. As these resources are being utilised at a much faster rate than their formation, they will...

Birds have undergone many structural adaptations to suit their aerial life. Some of these adaptations are as follows.  Streamlined body for rapid and smooth movement  Covering of feathers for insulation ...

Aves.  Specific feature of Aves is that they are warm –blooded having a four chambered heart and modified forelimbs for flight.

Some artists wanted their depiction of certain themes to reach the wider public. Hence, they wanted to produce cheap popular prints. Such prints must have helped in spreading certain ideas...

Both the energy sources, coal and petroleum, take millions of years for their formation. As these resources are being utilised at a much faster rate than their formation, they will...

Wash, peel, cut and cook the potatoes. Cooking in a small amount of water and then frying in a small quantity of oil conserves the nutrients.

Expansion of metal cap on heating.

"Napoleon had destroyed democracy in France but in administrative field, he had incorporated revolutionary principles in order to make the whole systems more rational and efficient." (i) All privileges based on...

Fitness refers to reproductive fitness (will leave more progeny) - more survival and hence selected by nature - natural selection 

(i) The average figures. hide the variations between trades and fluctuations from year to year. (ii) The real value of workers income fell significantly since the same wages could now buy...