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

[Q]: Sentence: 'two giraffes standing next to some trees'. Find frequency of the letter 'f'
[A]: 2


[Q]: Sentence: 'a bunch of cows that are in the field'. Find frequency of the letter 'a'
[A]: 3


[Q]: Sentence: 'kids with their parents playing in a room'. Find frequency of the letter 't'
[A]:
3