Final answer:
The correct weight/volume concentration of barium sulfate for a single contrast GI study is 60%, and for a double contrast GI study, it can go up to 100%.
Step-by-step explanation:
The weight/volume of barium sulfate for a single contrast gastrointestinal study (GI) is 60% and for a double contrast GI study, it can be up to 100%. Barium sulfate is a radiopaque contrast medium that coats the intestinal tract to provide enhanced visualization in radiographic studies. This substance is used in varying concentrations depending on whether a single or double contrast study is being conducted. Single contrast studies involve filling the GI tract with barium, which appears white on X-rays, outlining the stomach and intestines whereas, double contrast studies also involve the introduction of air or gas to further distend the GI tract, providing more detailed images.