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

[Q]: Sentence: 'oranges are sitting in a bowl on a table'. Find frequency of the letter 'a'
[A]: 5


[Q]: Sentence: 'a pizza is in a box on a table outside'. Find frequency of the letter 'u'
[A]: 1


[Q]: Sentence: 'guy leans on truck's hood while taking pics next to parked motorcycles'. Find frequency of the letter 's'
[A]:
4