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

[Q]: Sentence: 'a truck is parked in front of a store'. Find frequency of the letter 't'
[A]: 3


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


[Q]: Sentence: 'vases and a knitted bird are displayed on a shelf'. Find frequency of the letter 'a'
[A]:
6