فَهُوَ فِي عِيشَةٍ رَاضِيَةٍ
Then that person will enjoy a satisfying life. (101:7)
The fāʾ prominently introduces the response to ammā. Huwa is the nominal subject, the prepositional phrase «fī ʿīshah» serves as its predicate, and rāḍiyah modifies ʿīshah. The nominal construction depicts the resulting condition with stability.
Rāḍiyah is formally an active participle. One explanation understands it in the sense of marḍiyyah, 'pleasing'; another explains the attribution of satisfaction to the life itself as rhetorical extension. Both convey a life of satisfaction, but their grammatical accounts should not be collapsed.