Answer:
The time required to melt the frost is 3.25 hours.
Explanation:
The time required to melt the frost dependes on the latent heat of the frost and the amount of heat it is transfered by convection to the air .
The heat transferred per unit area can be expressed as:

being hc the convective heat transfer coefficient (2 Wm^-2K^-1) and ΔT the difference of temperature (20-0=20 °C or K).

If we take 1 m^2 of ice, with 2 mm of thickness, we have this volume

The mass of the frost can be estimated as

Then, the amount of heat needed to melt this surface (1 m²) of frost is

The time needed to melt the frost can be calculated as

Radon is <span>not a source of air pollution related to human activities</span>
Ion is an atom or molecule with a net electric charge due to loss or gain of one or more electrons.
The correct answer is option b, that is, triggered by changes in the weather.
Hibernation refers to a state of lower metabolism and inactivity usually witnessed in endotherms. This condition is featured by a slow heart rate, slow breathing, low metabolic rate, and low body temperature. It assists the majority of the endotherms to thrive in the cold seasons. For example, hibernation of a bear in winters. Therefore, weather change can stimulate hibernation.