Which phrase best defines a mountain eee

Option (D)

Explanation:

Mountain range refers to the chain of mountains and the different mountain ranges are separated from one another by rives and the valleys, that flows through them. These mountain ranges are formed by the  convergence of two continental plates, that forms a sandwich pattern, thereby forming huge mountain ranges, such as the Himalayas.

Thus, the correct answer is option (D).

i do not get it   at all

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.