Final answer:
The question involves determining the validity of expressions that resemble spreadsheet formulas. Expressions 3, 4, and 5 are valid, while expressions 1 and 2 are invalid due to incorrect syntax referencing.
Step-by-step explanation:
The question presented appears to relate to the syntax used in mathematical formulas, likely within the context of a spreadsheet software like Microsoft Excel or similar. Below are the statements and an evaluation of their validity.
- 1. = ab + ed - Invalid, because formulas typically start with an equals sign '=' and usually reference cells directly, such as '=A1+B1'.
- 2. = a3 - e5 - Invalid for the same reason as the first statement; the proper syntax would look something like '=A3-E5'.
- 3. =sum(a1:a5) - Valid, this is the correct syntax for summing values in cells A1 through A5.
- 4. =average(a1:a5) - Valid, this is the correct syntax for calculating the average of the values in cells A1 through A5.
- 5. =min(2,6,1) - Valid, this function correctly identifies the smallest number in the set provided.
The subject of these questions falls under Mathematics with a focus on the computations and operations as they relate to spreadsheet software, which is often introduced at the high school level.