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

[EX Q]: Sentence: 'two bigger elephants standing with a small elephant'. Find frequency of the letter 't'
[EX A]: 5

[EX Q]: Sentence: 'the two dogs are playing in the pen together'. Find frequency of the letter 'o'
[EX A]: 3

[EX Q]: Sentence: 'a mother and daughter playing a wii game'. Find frequency of the letter 'r'
[EX A]:
2