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

[EX Q]: Sentence: 'two men in black wet suits beside a white surfboard'. Find frequency of the letter 'e'
[EX A]: 5

[EX Q]: Sentence: 'a person is performing a stunt on a snowboard'. Find frequency of the letter 'p'
[EX A]: 2

[EX Q]: Sentence: 'two bucket sinks and mirrors reflecting a group of people'. Find frequency of the letter 'p'
[EX A]:
3