In the 1900s, sponge diving became a major industry in florida. this was possible because of methods brought by immigrants.

Greek immigrants

Explanation:

"Tarpon Springs" in Florida is known as the "Sponge Capital of the World." Many of the Greek people immigrated into the place in the year 1906. The reason behind this was that, they wanted to work in the sponge industry.

Sponges are naturally found in the place's ocean floor. From here, the Greeks were able to sell the natural sponges that they harvested. This made the industry thrive until today.

So, if you happen to visit this place in Florida, you'd be surprise with the existence of Greek culture such as their food and traditions.

Thus, this explains the answer.

i think its toxic gasses but i could be wrong

where is the rest of the question. this isn't making sense. can you upload a picture of the question?