In this task, you need to count the number of times the given letter appears in the given sentence.

[Q]: Sentence: 'people waiting on a train platform in a wooded area'. Find frequency of the letter 'p'
[A]: 3


[Q]: Sentence: 'a white police vehicle parked on a paved street'. Find frequency of the letter 'a'
[A]: 4


[Q]: Sentence: 'fuzzy photo of two trains going to the same direction of two of many tracks'. Find frequency of the letter 't'
[A]:
8