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 close up of a baby with a tooth brush'. How many words start with the letter 'a' in the sentence.
3

Sentence: 'horses are being walked around a race track'. How many words start with the letter 't' in the sentence.
1

Sentence: 'two people playing with a nintendo wii in a white room'. How many words start with the letter 'n' in the sentence.

1