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

[EX Q]: Sentence: 'soccer players on opposite teams fight for control over a ball'. Find frequency of the letter 't'
[EX A]: 4

[EX Q]: Sentence: 'tow birds flying by a long necked crane'. Find frequency of the letter 'f'
[EX A]: 1

[EX Q]: Sentence: 'a dog that is laying down in the sand'. Find frequency of the letter 'h'
[EX A]:
2