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

Sentence: 'a boy swinging a bat while playing baseball'. Find frequency of the letter 'h'
1

Sentence: 'a close up of a plate with a whole carrot'. Find frequency of the letter 'w'
2

Sentence: 'a little boy riding a yellow snowboard with a helmet on'. Find frequency of the letter 'b'

2