Answer:
A. 289 km²
Step-by-step explanation:
Your composite figure is a rectangle on top of a triangle.
The formula for the area of a rectangle is A = lw.
The formula for the area of a triangle is A = ½bh.
The formula for the total area is
A = lw + ½bh.
Data:
l = 17 km
w = 13 km
b = 17 km
h = 8 km
Calculation:
A = 17 × 13 + ½ × 17 × 8 = 221 + 68 = 289 km²
The area of the figure is 289 km².