Answer:
The answer is: a- and im-
Step-by-step explanation:
An affix is added to a root of a word in order to change its meaning, it can be added at the beginning (prefix) or at the end of the word (suffix).
In this case, the two affixes that mean without are a- and im-, they are both prefixes. An example using a- is amoral, which means without moral.
An example using im- is imposible, which means without possibility.