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

[EX Q]: Sentence: 'many white birds flying above a river that flows in front of a forest'. Find frequency of the letter 'a'
[EX A]: 5

[EX Q]: Sentence: 'a family out snow skiing on a blustery day'. Find frequency of the letter 'i'
[EX A]: 3

[EX Q]: Sentence: 'a blonde woman laying down on a bed with a laptop'. Find frequency of the letter 'i'
[EX A]:
2