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

Sentence: 'the street sign is next to a curved road'. Find frequency of the letter 's'
3

Sentence: 'hand holding a white calculator inside a store'. Find frequency of the letter 'o'
3

Sentence: 'two adults and one baby elephant walking in the woods'. Find frequency of the letter 't'

4