The fifth in a series of five problems that require algebra and/or geometry skills to solve.
Find the area of the red region and round to three decimal places. Let the digits of the area be represented by abc.def.
The cache can be found at: S41 1(b+c).e(a+b+c)(b+d) E173 0(a+d).f(c+f)e.
The cache contains only a log sheet. Bring your own pen.