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: 'an airplane as it is taking off and is ascending into space'. How many words start with the letter 'a' in the sentence.
[EX A]: 5

[EX Q]: Sentence: 'three people in suits are standing and holding surfboards'. How many words start with the letter 's' in the sentence.
[EX A]: 3

[EX Q]: Sentence: 'a grey cat stares through steel bars from window'. How many words start with the letter 's' in the sentence.
[EX A]:
2