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

Sentence: 'a woman standing in front of a bathroom sink in front of a mirror'. Find frequency of the letter 'o'
8

Sentence: 'a young man riding a skateboard near a forest'. Find frequency of the letter 'd'
2

Sentence: 'man making a sandwich behind a counter with a knife'. Find frequency of the letter 'o'

1