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 girl and her dog walk past a bike'. How many words start with the letter 'a' in the sentence.
[A]: 3


[Q]: Sentence: 'a number of motorcycles are on display at a museum'. How many words start with the letter 'o' in the sentence.
[A]: 2


[Q]: Sentence: 'a table with a pencil case cell phone a bag and coins'. How many words start with the letter 'a' in the sentence.
[A]:
4