I would just do for the first one 7/16 - 3/16 = 4/16 which is also 1/4 I'm not sure ho2 you estimate it
The area of the trapezoid would be 5/8 ft squared.
The staircase represents a constant rate of change because the height of the staircase is always going up or down, or changing. Each time the staircase goes up by a certain number, it always goes up by the same number and is therefore a constant rate of change.