Final answer:
From the list provided, 'dayOfWeek' and 'june1997' are legal variable names in programming because they start with letters and contain no illegal characters or spaces.
Step-by-step explanation:
The student's question concerns identifying the legal variable names in programming. When declaring variable names, there are general rules that most programming languages typically follow. Here is a breakdown of the options provided:
- dayOfWeek: This is a legal variable name. It starts with a letter and contains no illegal characters or spaces.
- 3dGraph: This is not a legal variable name because it starts with a number.
- june1997: This is a legal variable name because it starts with a letter and contains letter and numeric characters without any spaces or special symbols.
- mixture#3: This is not a legal variable name due to the inclusion of the '#' symbol, which is usually not allowed.
- week day: This is not a legal variable name because it contains a space, which is not allowed in variable names.
Therefore, the legal variable names from the list provided are 'dayOfWeek' and 'june1997'.