Final answer:
To determine which pen was used for a note, a forensic analysis can be conducted using ink analysis and microscopic analysis.
Step-by-step explanation:
To determine which pen was used for a note, a forensic analysis can be conducted.
One common test used in forensic science is ink analysis, which involves comparing the chemical composition and color of ink samples.
Other tests, such as microscopic analysis, can be used to examine the microstructure of the ink and determine its origin.