Heat flows naturally from a warmer object (higher energy) to a cooler one (lower energy).
A, 2 molcules
H2O is one molecule, it has 3 atoms (two hydrogen and one oxygen)
2 H2O are two water molecules
The answer is A) variable. The depression level is a value that varies with the respondents and may inform you about the relationship between depression and other variables, such as alcohol use or sleep habits. It is also likely a discrete variable, since the answer is probably an integer (1, 2, ... 10), rather than a continuous spectrum (virtually any number between 1 and 10).
