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 man pitching a baseball from a mound to a home plate'. How many words start with the letter 'a' in the sentence.
[EX A]: 4

[EX Q]: Sentence: 'a woman sitting in a chair next to a lot of vases'. How many words start with the letter 'a' in the sentence.
[EX A]: 3

[EX Q]: Sentence: 'a white horse stands at the side of a road pulling a carriage'. How many words start with the letter 'a' in the sentence.
[EX A]:
4