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.

Example Input: Sentence: 'a person is flying a kite in a field with other people in the distance'. How many words start with the letter 'w' in the sentence.
Example Output: 1

Example Input: Sentence: 'a shot of the tops of several tall buildings in a city'. How many words start with the letter 'a' in the sentence.
Example Output: 2

Example Input: Sentence: 'a close up view of a bright yellow sign by the road'. How many words start with the letter 'c' in the sentence.
Example Output:
1