Answer to Question 1
ANSWER: Students need to know that a radiation inversion is defined as the measured increase in air temperature just above the ground. It forms mainly through radiational cooling of the surface. Since radiation inversions occur on mostly clear, calm nights, they are also called nocturnal inversions.
Answer to Question 2
ANSWER: An appropriate student answer would be that small plants or shrubs may be protected from cold temperatures by covering them with straw, cloth, or plastic sheeting because this prevents ground heat from being radiated away to the colder surroundings. If you are a household gardener concerned about outside flowers and plants during cold weather, simply wrap them in plastic or cover each with a paper cup. On cold nights, certain crops can also be damaged by low temperatures. If the cold occurs over a widespread area for a long enough time to damage certain crops, the extreme cold is called a freeze.