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

[EX Q]: Sentence: 'a microwave oven with a yellow note on the door'. Find frequency of the letter 'w'
[EX A]: 3

[EX Q]: Sentence: 'two women standing next to each other holding tennis rackets'. Find frequency of the letter 't'
[EX A]: 7

[EX Q]: Sentence: 'many identical small boats in a shallow port'. Find frequency of the letter 'a'
[EX A]:
6