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.

Sentence: 'a crowd of people on the street one of which is taking pictures with a cell phone'. How many words start with the letter 'o' in the sentence.
4

Sentence: 'montage color photograph of helmeted motorcycle riders and a rural fire station'. How many words start with the letter 'r' in the sentence.
2

Sentence: 'two kids smile while standing on skis in the snow'. How many words start with the letter 's' in the sentence.

4