Read the following passage adapted from an essay on the history of underwater exploration technology:
In early 1942, French naval officer Jacques Cousteau sought a device that would allow divers to breathe underwater without tethered air lines. In December of that year, Cousteau traveled to Paris to meet engineer Émile Gagnan, who had designed a demand regulator for cooking-gas engines. During their initial meeting, Gagnan agreed to adapt his gas regulator for high-pressure compressed air tanks. By the spring of 1943, Gagnan completed the modified regulator prototype in his Paris workshop. In June 1943, Cousteau tested the prototype, dubbed the Aqua-Lung, in the quiet waters of the Marne River outside Paris. Following successful shallow trials, Cousteau transported the apparatus to the French Riviera in July 1943 to conduct deep-water ocean dives, reaching depths exceeding 100 feet. By autumn 1943, Cousteau and his team filed the official patent for the Aqua-Lung.
Based on the explicit details in the passage, in what chronological order did the key events in the development and testing of the Aqua-Lung occur?
- 1Cousteau met with Gagnan in Paris to discuss adapting a cooking-gas engine regulator.
- 2Gagnan finished building the modified regulator prototype in his workshop.
- 3Cousteau conducted initial tests of the Aqua-Lung in the Marne River.
- 4Cousteau completed deep-water ocean dives off the French Riviera.
- 5Cousteau and his team submitted the official patent application for the Aqua-Lung.