Final answer:
The RMS Titanic sank on April 15, 1912, not May 7, 1915, which is the date when the RMS Lusitania was sunk by a German submarine.
Step-by-step explanation:
The RMS Titanic was not the ship that sank on May 7, 1915 — that was the RMS Lusitania. However, if you meant to ask about when the RMS Titanic sank, the date was April 15, 1912. The Titanic hit an iceberg on its maiden voyage from Southampton to New York City and sank in the North Atlantic Ocean. While the Lusitania's sinking, caused by a German submarine, also had significant impact on history, particularly because it carried American passengers, it is a separate event and should not be confused with the disaster of the Titanic.