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

[Q]: Sentence: 'a girl laying on a bed posing for a picture'. Find frequency of the letter 'i'
[A]: 4


[Q]: Sentence: 'surfboard being displayed in stor window with clothes behind it'. Find frequency of the letter 't'
[A]: 4


[Q]: Sentence: 'three people on snowboards jumping a snowy hill'. Find frequency of the letter 'h'
[A]:
2