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: 'a young boy hits a baseball during a game'. How many words start with the letter 'd' 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 dog with a book in front of the dog'. How many words start with the letter 'b' in the sentence.
[EX A]:
1