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

[EX Q]: Sentence: 'cars parked outside if a retail store'. Find frequency of the letter 'd'
[EX A]: 2

[EX Q]: Sentence: 'a couple is cutting in to a cake at a wedding'. Find frequency of the letter 'd'
[EX A]: 2

[EX Q]: Sentence: 'people with bags are approaching a white airplane'. Find frequency of the letter 't'
[EX A]:
2