What is the length b, in meters, of the rectangular lawn shown?

To determine the length ( b ) of the rectangular lawn, we need additional context or measurements that relate to the options given (A, B, C, D). If you have a particular method or formula in mind—such as using perimeter, area, or other dimensions—please share that information.

Without specific measurements or a diagram, I cannot provide the correct answer. Please refer to the materials associated with your question for the relevant information, or feel free to check the extended services page for further assistance.