The heart has 2 chambers: The UPPER CHAMBERS are called the and the LOWER CHAMBERS are called the a
valves, septum
b
right, left
c
atrium, ventricles
d
top, bottom

The heart has 2 chambers: The UPPER CHAMBERS are called the atrium and the LOWER CHAMBERS are called the ventricles

Therefore , answer is c

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