In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

[EX Q]: Sentence: 'two elephants with people riding on them next to block barriers'. How many words start with the letter 'o' in the sentence.
[EX A]: 1

[EX Q]: Sentence: 'a man on a beach throwing a frisbee while two people walking the water'. How many words start with the letter 'a' in the sentence.
[EX A]: 3

[EX Q]: Sentence: 'a red and yellow fire hydrant in an open field'. How many words start with the letter 'a' in the sentence.
[EX A]:
3