What is the formula to determine unit rise when there are two flights of stairs?

To determine the unit rise for two flights of stairs, the appropriate formula involves dividing the total rise by the number of flights. In this case, since there are two flights, the total rise should be divided by two. This gives the height that each individual flight needs to rise to achieve the overall total elevation.

Unit rise represents the height gained from one level to another level for each flight of stairs. By using the total rise divided by the number of flights, you ensure that the rise is equally distributed across the two flights, providing a consistent and safe measurement for construction.

The other options do not accurately represent how to calculate the unit rise in this context. For instance, multiplying the total rise by two would yield a value that is not applicable since you need to find how much each flight rises, rather than inflating the total. Adding or subtracting a constant figure like two also does not reflect any meaningful relationship between the total rise and the required rise per flight.