The number of guests at a ski resort on any given day is related to the day's high temperature. If the high temperature is -20°F or below, no one comes
to the resort. As the temperature increases, so does the number of guests.
Once the temperature reaches 0°F and increases through the single digits,
the number of guests soars. If the temperature is 10°F or higher, the ski
resort is at full capacity with 400 guests.