Final answer:
The correct expression that simplifies to 1/π18 is option b) 1/18π. This is because when we separate the terms, the expression becomes (1/18)(1/π), which simplifies to the desired expression.
Step-by-step explanation:
The student's question is about simplifying a mathematical expression to obtain the result 1/π18. To find the correct expression among the options provided, we need to consider the properties of multiplication and division involving π. The expression 1/18π can be rewritten as (1/18)(1/π) which simplifies to 1/π18 since multiplying the fractions with the numerator as 1 will simply involve multiplying the denominators.