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

Sentence: 'a double decker transit bus parks by a blue on the side of the street in front of a brick building in the city'. Find frequency of the letter 't'
9

Sentence: 'two people and two children walking in a building'. Find frequency of the letter 'd'
3

Sentence: 'a bird is standing on the ledge of the building'. Find frequency of the letter 't'

3

