गहराई बढ़ने के साथ महासागरीय जल के घनत्व में तीव्र परिवर्तन या प्रवणता को क्या कहा जाता है?

In which geographical area is the world's largest accumulation of marine plastic debris, known as the Great Pacific Garbage Patch, located?

Consider the following pairs: Oceanic Trench — Ocean I. Mariana Trench — Pacific Ocean II. Tonga Trench — Indian Ocean III. Peru-Chile Trench — Pacific Ocean IV. Puerto Rico Trench — Atlantic Ocean How many of the above pairs are incorrectly matched?