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

[EX Q]: Sentence: 'two bears swim in a blue pool of water'. Find frequency of the letter 'o'
[EX A]: 4

[EX Q]: Sentence: 'some sheep are standing in a grassy field'. Find frequency of the letter 'n'
[EX A]: 3

[EX Q]: Sentence: 'a skier in mid air on a ski slope'. Find frequency of the letter 'r'
[EX A]:
2