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

[Q]: Sentence: 'a plane with stairs next to it sitting in a large lot'. Find frequency of the letter 'i'
[A]: 6


[Q]: Sentence: 'a little child looking up to a camera holding a cell phone'. Find frequency of the letter 'g'
[A]: 2


[Q]: Sentence: 'a baseball player walking across a field while holding a bat'. Find frequency of the letter 'd'
[A]:
2