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

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

Sentence: 'a person holding a wine glass in one hand and bread sticks in the other'. Find frequency of the letter 'd'
4

Sentence: 'a red fire hydrant in the middle of dirt'. Find frequency of the letter 'o'
1