: In the study by Silver and Aiello, an objective was to determine if the frequency of falls was independent of wheelchair use. Do these data provide sufficient evidence to warrant the conclusion that wheelchair use and falling are related? Let level of significance 0.05. The following table gives the data for falls and wheelchair use among the subjects of the study.

i believe it would cause an increase of percipitation, though i could be wrong. so i would say b is the answer.

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.