Final answer:
The correct formula to determine the number of newspapers Abby will need for each floor is f = number of floors * a = number of newspapers per floor. This formula calculates the total number of newspapers needed by multiplying the number of floors by the number of newspapers per floor.
Step-by-step explanation:
The correct formula to determine the number of newspapers Abby will need for each floor is f = number of floors * a = number of newspapers per floor.
For example, if Abby has 5 floors and she needs 10 newspapers per floor, the formula would be: f = 5 * 10 = 50 newspapers.
This formula calculates the total number of newspapers needed by multiplying the number of floors by the number of newspapers per floor.