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

[Q]: Sentence: 'there is a baseball game on and a few people are watching'. Find frequency of the letter 'i'
[A]: 2


[Q]: Sentence: 'statues of 2 zebras and 1 giraffe in a doorway'. Find frequency of the letter 'a'
[A]: 6


[Q]: Sentence: 'a plate on a table holds two donuts'. Find frequency of the letter 'u'
[A]:
1