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 person sitting on a stone wall using a cellular phone'. How many words start with the letter 's' in the sentence.
[EX A]: 2

[EX Q]: Sentence: 'a group of parked bikes sitting on the side of a road'. How many words start with the letter 'o' in the sentence.
[EX A]: 3

[EX Q]: Sentence: 'a bunch of random do it yourself items on a table'. How many words start with the letter 'r' in the sentence.
[EX A]:
1