Select all the situations for which only zero or positive
solutions make sense.

Measuring temperature in degrees Celsius at an Arctic
outpost each day in January.
The height of a candle as it burns over an hour.
buns
The elevation above sea level of a hiker descending into a
canyon.
The number of students remaining in school after 6:00 p.m.
The temperature in degrees Fahrenheit of an oven used on a
hot summer day.