It's been a long time since the last problem, and I will attempt to revive this practice. It was created with the purpose of posting some interesting problems for students who prepare for Olympiads, but, anyone interested can attempt solving. Who solves it correctly, may post the next practice problem.
This problem was particularly interesting for me. Here it is:
Draw the structural formulae of the hydrocarbons I-V, which correspond to the characteristics presented in the table below (in each case one solution is sufficient). The table is attached. Good luck.