The trick in here is to break the composite figure into parts.
1. Calculate area of the circle
5.1^2*pi*(120/360) = 27.24
2. Calculate area of the rectangular prism
5.1*3.2 = 16.32
3. Calculate the are of the triangle
5.1*(7.4-3.2)*0.5 = 10.71
4. Add them up
27.24 + 16.32 + 10.71 = 54.27
Answer: 54.27
