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

Sentence: 'a closeup view of a bathroom sink, that is very modern'. Find frequency of the letter 'e'
4

Sentence: 'some cubbies with towels in a blue bathroom'. Find frequency of the letter 'l'
2

Sentence: 'a boat is docked next to a walkway on the water'. Find frequency of the letter 'd'

2