Find out a qualitative test for proteins, fats and oils, amino acids and test any fruit juice, saliva, sweat and urine for them.

Explanation

To find qualitative tests for proteins, fats and oils, and amino acids, and to test any fruit juice, saliva, sweat, and urine for them, we can follow these steps:

### Step-by-Step Solution:

1. **Qualitative Test for Proteins (Biuret Test)**:
- **Procedure**: Take a sample of the liquid (fruit juice, saliva, sweat, or urine) you want to test. Add a few drops of Biuret reagent to the sample.
- **Observation**: If the solution changes from light blue to purple, it indicates the presence of proteins.

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