Which sentence from exploring the titanic indicates a shift in tone? as we settled in to the new ship, tension began to mount. i thought that this must have happened when the titanic sank. i also hoped that cameras would succeed where sonar had failed. the smell of hot buttered popcorn filled the room.

As we settled in to the new ship, tension began to mount.

Explanation: according to Edge

I also hoped that cameras would succeed where sonar had failed.

Explanation:

In this sentence, the verb "hope" begins the sentence with a positive tone that cameras will be successful. However, we see a change of tone in the second part when we are presented with the idea that sonar had previously failed. Positivism in the first part and negative in the second part of the sentence.