Answer: well and out.
Step-by-step explanation:
Adverbs are describing and modifying a noun, adjective or another adverb. In this sentence, the adverb is ''well'' because it is telling us how they lifted their heads(noun).
This word can be also used as an adjective(when it is used to describe a condition).
The other adverb is ''out'' and this word is mostly used as a proposition. In this case, adverb ''out'' is modifying another adverb ''well''.