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 clock tower is standing next to palm trees'. How many words start with the letter 't' in the sentence.
Example Output: 3

Example Input: Sentence: 'cars and a motorcycle waiting at an intersection'. How many words start with the letter 'a' in the sentence.
Example Output: 4

Example Input: Sentence: 'busy thumbs type a text message on a mobile phone'. How many words start with the letter 't' in the sentence.
Example Output:
3