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

Sentence: 'a few giraffes standing in a field looking around'. Find frequency of the letter 'e'
3

Sentence: 'a bus with two floors belonging to london country'. Find frequency of the letter 't'
4

Sentence: 'a jet flying over an airport tarmac under a cloudy blue sky'. Find frequency of the letter 't'

3