Fill the gap

Sea water contains ________ of oxygen contained in fresh water stream:-

Concepts:

1. In general, dissolved oxygen levels are about 20% less in seawater than in fresh water.

2. Sea water contains, by weight, about 3.5 percent dissolved salts, whereas river water has only 0.012 percent.

Note:

1. Dissolved oxygen is usually measured in milligrams per liter (mg/L) or as a percent of air saturation. However, some cases it is measured in parts per million (ppm) or in micromoles (μ mol).

2. One micromole of oxygen is equal to 0.022391 milligrams, and this unit is commonly used in oceanic studies.