There are commas missing in the following sentences. can ya me find where.

1. The race, therefore, was equally challenging  to all the contestants.

2. Are you going to join us for tea, Mrs. Collins?

3. The rowers, of course, were exhausted after the three-hour race.

i think its,

b) the narrator's mental state is anguished.

happy to

pls mark as brainliest