When using a spectrophotometer, the properties that change depending upon the concentration of solute in the sample are:
1. **Absorbance** - According to Beer-Lambert Law, absorbance is directly proportional to the concentration of the solute in the solution.
2. **Transmitted light** - As the concentration of the solute increases, the amount of light that is transmitted through the sample decreases, since more light is absorbed.
The other options, **the amount of sample loaded onto the spectrophotometer** and **incident light**, do not directly change with the concentration of the solute:
- **The amount of sample loaded onto the spectrophotometer** is typically determined by experimental design and fits within the cuvette, rather than the concentration of the solute.
- **Incident light** refers to the light that is emitted from the spectrophotometer source and does not vary with the concentration of solute in the sample.
Thus, the correct answers are **absorbance** and **transmitted light**.