Question

answer the following in two or three sentences
1) list out the causes of air pollution

2) why are manure and fertilizers used in fields

3) how does an amoeba obtain it's food.

4) how many types of elements together make up the xylem tissue? name them.

5) write any two characters of Mammalia.

6) state first law of motion

7) what are the importance of universal law of gravitation

8) what is potential energy give example

Answer 1

air pollution :uses of vehicles in large numbers.
: deforestation.
manures :to increase hold water capacity.
: these are natural.
fertilisers :these are chemicals.
:to increase production.
mammalia: those who give birth
: feed milk to their young ones

Answer 2

And.#6→ sometimes referred to as the law of inertia. An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Ans.#3 → (see diagram)

And.#2→ Manures r used to improve the fertility naturally.Manures r made up of naturally decaying substances like dead,winter leaves,flowers,compost,cow dung etc.It takes a long time for soil to obtain fertility in this process.

Fertilizers r chemicals which helps to improve soil ferlity too but the process is faster than manure.Since these r chemically manufactured,they should not be used excessively or else they will cause soil nd water pollution.

And.#8→An object can store energy as the result of its position. For example, the heavy ball of a demolition machine is storing energy when it is held at an elevated position. This stored energy of position is referred to as potential energy. Similarly, a drawn bow is able to store energy as the result of its position.