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 riding on top of a wave on a surfboard'. How many words start with the letter 'o' in the sentence.
[EX A]: 3

[EX Q]: Sentence: 'a group of people sitting at a restaurant table'. How many words start with the letter 'a' in the sentence.
[EX A]: 3

[EX Q]: Sentence: 'a computer desk with a computer monitor and keyboard on top of it'. How many words start with the letter 'o' in the sentence.
[EX A]:
2