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

[EX Q]: Sentence: 'a girl that has a kite in the air'. Find frequency of the letter 'r'
[EX A]: 2

[EX Q]: Sentence: 'a person riding a camel in front of a truck'. Find frequency of the letter 't'
[EX A]: 2

[EX Q]: Sentence: 'a giraffe stands tall in a grassy meadow'. Find frequency of the letter 'a'
[EX A]:
7