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

[Q]: Sentence: 'a boy catching a frisbee while standing ins bunch of leaves'. Find frequency of the letter 'a'
[A]: 5


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


[Q]: Sentence: 'a girl playing on her ipad while laying on her bed'. Find frequency of the letter 'g'
[A]:
3