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 husky is sleeping while wearing a green bandana'. How many words start with the letter 's' in the sentence.
Example Output: 1

Example Input: Sentence: 'a man and three children playing with a kite on the grass and other people riding bikes on a nearby road'. How many words start with the letter 'a' in the sentence.
Example Output: 5

Example Input: Sentence: 'a girl skier rests against a tree on a snowy trail'. How many words start with the letter 't' in the sentence.
Example Output:
2