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.

Q: Sentence: 'a woman in a black tennis outfit playing tennis on a red clay court'. How many words start with the letter 'r' in the sentence.

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

A: 1
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Q: Sentence: 'an elevated train on a bridge in front of buildings'. How many words start with the letter 'o' in the sentence.

A:
2
****