Ballard did not know exactly where the Titanic's wreak was located. How did he overcome this problem. (Need answer and Explanation)

The following is an exerpt from “Finding The Titanic“

(from Planet-Science.com)

”The traditional way to search for wrecks was to use sonar. Sonar uses sound to detect objects underwater. As well as using sonar, Ballard searched for the Titanic's trail of debris. He estimated that it would be over 2km long. Ballard had just 12 days to find it, in an area of ocean five times the size of New York.

To find the trail, Ballard used a deep-sea vehicle called Argo. Argo had lots of cameras and was towed behind the ship. Argo floated just above the sea floor, 2.5 miles down in the cold, dark Atlantic.

After days of searching, Ballard found the trail. He knew the currents would take the trail northwards. Ballard followed the trail and sailed right up to the Titanic!”

d. murder of a son and cooking the son for a feast

procne murdered her son and served him to tereus, her husband and her son's father. she did this out of revenge. tereus raped her sister, philomela, and cut her tongue out to keep her from talking. philomela managed to communicate it to procne and procne sought revenge.

tantalus murdered his son and fed him to the gods because he was angry with the gods. the gods punished him by putting him in a pool of water that evaporates when he tries to drink and having fruit hang just out of his reach.