From September 2022:

For (c) I answered with what in (d) is represented in path S0(S2ˆ(omega)) to satisfy formula S2. Is that correct?

Then in (d) I am confused by the answer, how can {s0,s2} satisfy S2?

I thought it would hold if the initial state was directly s2.

I read the formulas as:

S1: There exists a path where eventually a is strong until b

S2: There exists a path where exists a path where eventually a is strong until b

Is something wrong with my understanding?

Thank you in advance