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

[EX Q]: Sentence: 'a table topped with a cupcake on a picture of a cupcake'. Find frequency of the letter 'o'
[EX A]: 3

[EX Q]: Sentence: 'there is an old stove with old pots on the burners'. Find frequency of the letter 't'
[EX A]: 5

[EX Q]: Sentence: 'giraffes big and small roaming around in their natural habitat'. Find frequency of the letter 'a'
[EX A]:
9