Answer: Option (a) is the correct answer.
Explanation:
The stream that flows during or after the rainfall is called an ephemeral stream. This stream occurs in areas where there is less rainfall or deficiency of moisture.
The stream that flows only in flat lands is called as river.
Mechanical weathering results in the breaking of rocks causes ice wedging.
Chemical weathering results in the change in molecular structure of rocks and soil.
Thus, it can be concluded that option (a) is the correct answer.
Ice floats after it crystallizes because ITS DENSITY IS LESS THAN THAT OF WATER.
When a quantity of water is cools down by reducing its temperature, the molecules of the water lose kinetic energy and slow down in their movement. As the water is cooling down, it is volume is expanding. When the temperature reaches zero degree Celsius, the water becomes ice. At this point, the ice can float on water because its density is less than that of water; this is as a result of the spaces that now exist in the ice structure.
Answer:
2 atoms of nitrogen are present.
