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.
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Question: Sentence: 'a blue brick building with a man leaning on it'. How many words start with the letter 'b' in the sentence.

Answer: 3


Question: Sentence: 'some signs and the roof of a train station'. How many words start with the letter 'a' in the sentence.

Answer: 2


Question: Sentence: 'a group of people standing around an airplane on top of a field'. How many words start with the letter 'a' in the sentence.

Answer:
5