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

[EX Q]: Sentence: 'a castle like bed room that has the era of templar knight similarities'. Find frequency of the letter 'm'
[EX A]: 3

[EX Q]: Sentence: 'a person standing operating a cell phone in a room'. Find frequency of the letter 'n'
[EX A]: 6

[EX Q]: Sentence: 'a boat in the water some buildings and hills'. Find frequency of the letter 'i'
[EX A]:
4