Line Coupler Problem

Hi,

There is a simple question of Coupled line coupler, I am a bit confused how to solve this question.(Picture is attached)
If anyone knows the solution, please let me know, your help is always appreciated,
Thank you

First, set the Width, gap, freq, lamda/4, etc. from the Zoo and Zoe.
The result is, when L=lamda/4, the output is about -17.8dBc to input.
When L=lamda/2, the output is about -17.3dBc to input.

Thanks so much :)

I really wanted to know how to solve this problem :/

Setup a coupled line model, set freq, trace width, trace gaps etc., so that Zoo and Zoe meet the requirements.
Then simulate with software.