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

[EX Q]: Sentence: 'a couple of people that are on a baseball field'. Find frequency of the letter 'c'
[EX A]: 1

[EX Q]: Sentence: 'a girl laying on a bed posing for a picture'. Find frequency of the letter 'i'
[EX A]: 4

[EX Q]: Sentence: 'a pizza has various toppings on its surface'. Find frequency of the letter 'h'
[EX A]:
1