Final answer:
Cannot determine the note under the red arrow without a diagram or additional context, as identifying musical notes requires visual information or a reference to musical terms.
Step-by-step explanation:
Without the provided diagram or additional context, it's impossible to accurately name the note under the red arrow. In order to identify musical notes, visual information such as notation on a staff or a reference to musical terms is required.
Identifying notes typically involves understanding their position on a musical staff, which consists of five lines and four spaces, with each line and space representing a different musical pitch. For example, if the red arrow points to a note on the second line of the treble clef staff, it would be an 'G' note. However, without a specific diagram, further assistance cannot be provided.