Answer: The three sentences that indicate that the passage is an ex nihilo type of creation story are:
"There was as yet no man, nor any animal, nor bird, nor fish, nor crawfish, nor any pit, nor ravine, nor green herb, nor any tree; nothing was but the firmament."
"The face of the earth had not yet appeared-only the peaceful sea and all the space of heaven."
"There was nothing yet joined together, nothing that clung to anything else; nothing that balanced itself, that made the least rustling, that made a sound in the heaven."
Explanation: These sentences suggest that before the creation event described in the passage, there was nothing but the firmament and the peaceful sea, and that the creation process involved the creation of everything that exists, including the earth, animals, plants, and other features of the world. This is a hallmark of ex nihilo creation stories, which depict the creation of everything from nothing.