For the existential quantifier, yes. We could then form an infinite path going through s8. s8 satisfies a&c. Thus, the infinite path from s0 satisfies F (a&c). Hence, the state s0 satisfies E F (a&c). But it does not satisfy A F (a&c) because we still have infinite paths (the one between s0 and s2 for example) that do not satisfy F (a&c).