Ответ: 1) a new flat is being bought by my father.

2) food is being cooked by the chef in the restaurant

3) the problem is being solved by the teacher.

давай сам/сама тож поробуй!!.

Ты справишься♡

Объяснение: Obj+ is/are being V2

Ставишь не subject, а object !

например:

Sam is cooking the big cake (активный залог)

The big cake is being cooking by Sam (пассивный залог)