Frost wedging happens when
water ions dissolve rock minerals
water freezes inside a rock, causing it to break
oxygen reacts with the chemicals in rock
rocks break from repeated exposure to the sun's heat

water freezes inside a rock, causing it to break

Weathering is a natural process in which the rocks break into pieces or sediments by the action of wind, water and chemical agents. Frost wedging is a physical weathering process. It occurs in an area where temperature fluctuations occurs due to change in the climatic conditions. This occurs due to rapid heating and cooling. The rocks lying in a cold environment, the water residing in the rocks gets freezed. The water in ice form that is solid form acquire more space than in liquid form, therefore, the developed ice will affect the physical structure of the rock. The formation of ice results in the development of break or crack in the rock typically in the shape of a wedge and thus the phenomena is called as frost wedging.

Hence, frost wedging happens when water freezes inside a rock, causing it to break.

answer: option c. i.e. electric current flowing “downhill” from the negative electrode to the positive electrode in a battery

explanation:

the water analogy to the circuits define the pipes (water flows) to the electric current. now, we know that the electric current flows from the positive terminal to the circuit (as shown in the diagram attached).

hence, option c is the correct answer.