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

Sentence: 'girls posing of a picture one holding a tennis racket the other wearing a crown'. Find frequency of the letter 'g'
4

Sentence: 'a stuffed animal sitting on an empty bed'. Find frequency of the letter 'u'
1

Sentence: 'some tan furniture in a large home livingroom'. Find frequency of the letter 't'

2