Question

she was cooking lunch (change the voice)​

Answer 1

Answer:

lunch was cooked by her

Answer 2

Lunch was being cooked by Her .

to convert active to passive voice we have to kept in mind

observe the given sentence it is active or passive.

Given question is in active .

observe the tense of the sentence.

It is in simple past participle tense .

Change subject into subject and subject change into object.

Verb is in past participle so being is used and change it in to V3 form .