Answer:
The baseball whizzed by my bat and the umpire called "Strike!" The crowd was silent but nervous as the pitcher prepared to throw what could be the final pitch of the championships.
Step-by-step explanation:
The word nervous fills the space correctly, since the meaning of nervous is to be agitated and a little bit anxious with is quite opposite from the word silent that shows a state of not making any sound, the word but is a connector we use to present contrast so the people were tense and expectant but they didn't make a fuss about it.