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

Sentence: 'a jet flying through the clear blue sky'. Find frequency of the letter 'g'
2

Sentence: 'a little boy sitting on a bed in a bedroom'. Find frequency of the letter 'e'
3

Sentence: 'this young lady is in her hospital bed opening mail'. Find frequency of the letter 'g'
2