Nope, sure don't sesrch it on amazon or something. Maybe youll find one and be able to but it.
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.
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical equation for reaction of potassium superoxide with carbon dioxide to produce oxygen and potassium carbonate will be:

H2O (water) has 2 hydrogen atoms and 1 oxygen atom.