Is Matter Around Us Pure ? — Science STD 9 — Question

Growing different crops in the same field in a pre-planned succession, to improve the quality and quantity of the crop yield and maintain the fertility of soil is known as:

Water will be absorbed by the root hair because:

Cells and their surrounding cell membrane are usually very small because:

Does the force of gravitation exist between two astronauts in space:

Husk of coconut is made of:

‘Note’ os a sound:

Smallest possible unit of a compound which has independent existence is:

Which of these is not related to endoplasmic reticulum?

Plasma membrane is:

Two chemical substances X and Y combine together to form a product P which contains both X and YX + Y → P
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following statements concerning X, Y and P are correct?

1. P is a compound.
2. X and Y are compound.
3. X and Y are elements.
4. P has a fixed composition.