Help me..In these MCQ'S.
. #No spam..

1)Biodiversity of an area refers to the vast number of species of plants, animals and microorganisms existing in that  area.

2)Fauna refers to animals, whereas flora refers to plants

3)Yes, I agree with the statement. Forests provide plant cover to check the flow of water. If forests are removed, then  floods will occur.

4)False.

Endangered animals are those species whose numbers are diminishing at an alarming rate and face an immediate  danger of extinction.

5)If all trees in a forest are cut, it will lead to erosion of soil.

6)Grazing by cattle should be controlled for forest conservation.

7)True.

Soil erosion is the removal of top layer of soil that is most fertile. If not checked, soil erosion ultimately leads to  desertification.

8)The flora and fauna of a country are among the most important renewable natural resources.

9)Dinosaurs are extinct because no living member of this species is present on earth.

10)Wildlife conservation and forest conservation are closely related.

11)False.

A biosphere reserve comprises of three core areas: natural zone, buffer zone and transition zone. These zones are  not present in a tiger reserve.

Explanation:

Peace

spiders belong to a group of arachnids.

arachnids have the following traits :

they have two body parts.

they have eight legs unlike insects which have 6 legs.

they have no wings.

these traits distinguish them from insects.

the information that antonio is doubting us the statement that spiders differences are as a result of being first to evolve.

this is because the evolution of one species is independent of the other species.

answer: zinc is the substance which has a volume of 1.38 .

density is defined as the mass of an object per unit volume.

it can be calculated by dividing mass of a substance by its volume i.e.

si unit of density is kg per cubic meter and cgs unit of the same is gram per cubic centimeter.

now from the given data volume can be calculated by the formula .

hence, the volume of aluminium will be = which comes out to be 1.703 .

similarly, volume of zinc, chromium, and nickel will be 1.378 , 0.869 , and 0.356 respectively.