Any temperature on the kelvin scale can be changed to celsius degrees by
a. subtracting 100 from it.
b. adding 212 to it.
c. subtracting 273 from it.
d. subtracting 32 from it.

c) should be the answer.

if the temperature drops and becomes cool

then the atmosphere can be freezing as the water vapor in the air is at maximum (100%) and can be severely cold

also can be snowing lightly as the moisture in the air will start to solidify

and btw this is not chemistry but