Answer: C- ecosystem
An ecosystem is a biological community in which living beings interacts with their non-living environment. An ecosystem consists of abiotic ( non-living factors like water, sunlight, wind and soil) and biotic factors such as plants and animals. Ecosystem allows not only the interaction of abiotic and biotic factors but it favors the interaction between the living species. For example animals are dependent upon plants so as to derive their food. The coexistence of organisms favors the diversity of land forms on earth.
Communities of organisms coexist in organized, balanced ecosystems.
Answer:
The SI units of A, B and C are :
Explanation:
The position x, in meters, of an object is given by the equation:

Where
t is time in seconds
We know that the unit of x is meters, such that the units of A, Bt and
must be meters. So,


So, the SI units of A, B and C are :

So, the correct option is (B).
Answer: Wet barometer - The tool works by measuring atmospheric pressure to predict incoming weather. Since the glass is only filled halfway with water, the other half is exposed to the atmosphere. When the outdoor atmospheric pressure rises, the pressure in the glass decreases, and causes the water to move down the spout.
Dry barometer - A Torricellian barometer (sometimes called a mercury barometer) is an inverted (upside-down) glass tube standing in a bath of mercury. Air pressure pushes down on the surface of the mercury, making some rise up the tube. The greater the air pressure, the higher the mercury rises.
I hope this helps!