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

[EX Q]: Sentence: 'a teddy bear is sitting on a heart shaped patio chair outside'. Find frequency of the letter 'i'
[EX A]: 6

[EX Q]: Sentence: 'a notebook and pen are left on a park bench'. Find frequency of the letter 'e'
[EX A]: 5

[EX Q]: Sentence: 'a woman standing next to a window talking on a cell phone'. Find frequency of the letter 'o'
[EX A]:
5