tl;dr Answer is C
Here we will have to calculate 3 different areas separately.
When calculating the area of the triangle we will use the formula
A = (h*b)/2
A = Area
h = height
b = base
To find the height we do X - Z
23 - 15 = 8 ft
To find the base we do Y - W
19 - 13 = 6 ft
Using the formula above we can now solve for A
A = (8*6)/2
A = (48)/2
A = 24 sq ft
Now we solve the two rectangles using the formula
A = wl
w = width
l = length
We will calculate the area of the left most rectangle first.
We know the length of the rectangle because it's Y - W and we are given the width of the triangle.
w = 15 ft
l = 6 ft
A = 15*6
A = 90 sq ft
Second Rectangle has the width of X and length of W
w = 23 ft
l = 13 ft
A = 23 * 13
A = 299 sq ft
Now we add all the areas to give us the total area of the warehouse.
24 + 90 + 299 = 413 sq ft
Therefore, the answer is C