Modal Ability: could have vs was able to / managed to (B1)

After three hours of searching, the firefighters ___ rescue all the people trapped inside.

She ___ finished the exam early, but she decided to check her answers again.

The password was very complex, but he ___ remember it without writing it down.

You ___ asked me for help — I was free all afternoon.

The surgeon ___ perform the operation successfully despite the power cut.

Despite trying for hours, the engineers ___ fix the server in time.

I ___ taken a different route, but I didn't know about the traffic.

Even with a broken arm, the climber ___ reach the summit.

They ___ invested in that company years ago — it's worth millions now.

After months of practice, she ___ play the piece from memory at the recital.

The report contained errors that the editor ___ caught before publication.

The ship was sinking fast, but the captain ___ guide it safely into port.

You ___ told me the meeting was cancelled — I waited for an hour!

The negotiators talked for eight hours and finally ___ reach a compromise.

We had all the ingredients, so we ___ made the cake ourselves instead of buying one.