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

[Q]: Sentence: 'a woman in a tank top reaches out for a frisbee'. Find frequency of the letter 'a'
[A]: 6

[Q]: Sentence: 'food sitting in bowls on table with checked tablecloth'. Find frequency of the letter 't'
[A]: 6

[Q]: Sentence: 'a couple of animals that are in the grass'. Find frequency of the letter 'u'
[A]:
1