Organisms are made up of a bunch of cells. Billions of cells coming together make up an organism.
The answer is D. In a
geological era, when the plants and animals
in the then environment die, they get buried
in sediments. These sediments are covered
by other sediments of another geological
time within which are the remains of dead species
of the then geological era. These sediments from different geological times have different properties hence
form visible strata that can be studied to identify the kind of environment in the then geological time. Their
fossils can also be studied to identify
the kind of species that roamed the earth during the time.
Weather change, the air density l, the way the animals are acting and satlities
Production of energy using water power
Using electricity or energy-saving products, creation of technology to capture sulfur dioxide are the processes that can be taken into account.
<h3><u>Explanation</u>:</h3>
Acid rain is a very serious issue in the urban areas now a days. Acid rain forms due to the excessive production of gases like sulphur dioxide, nitrogen oxides etc which are beyond the level of absorption by the environment. This gases go up in the atmosphere and they mixes with cloud water to form corresponding sulphuric acid and nitric acid. These acids come along the rain and decrease the pH of the water bodies as well as soil.
If we start using water as the source of our energy production, then we can eliminate the use of coal and other fossil fuels which are chief sources of these gases.
If we can grow some technology to capture these gases before they are released into the environment, then also there will be less problems. Technologies like alkali bath are not so operative in large scales.
We can use electricity in boilers and other places where still, fossil fuels are brunt to produce the heat so that sulphur oxides don't come out.