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

Sentence: 'a person on a skateboard going down a ramp'. Find frequency of the letter 'n'
4

Sentence: 'two people are riding on canoes down a river'. Find frequency of the letter 'e'
5

Sentence: 'the pizza has various meaty toppings on it'. Find frequency of the letter 'h'

2