Which perfect verb tense is used for an action that happened in the past that stopped or ended before another action (that is also already over) started?

As of this moment, I ___________ everything you asked me to do. (a. have completed b. had completed c. will have completed)

Change this active sentence into passive voice: News reports are written by the reporters.

She ______________ finished her homework before I offered to help. (a. have completely b. had completely c. will have completely)

Change this passive sentence into active voice: The thief has been caught by the police.

I went to the park yesterday.

You will regret this.

Change this passive sentence into active voice: Some advice will be given to you by Doctor Brown.

Change this active sentence into passive voice: I will never forget this experience.

Change this passive sentence into active voice: Some trees have been planted by the gardener.

They ___________ duty since 8 a.m. (a. had been performing b. have been performing)

John _________________ to travel to California next month, but he now can’t afford a plane ticket. (a. have planned b. had planned c. will have planned)