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

[Q]: Sentence: 'a woman is taking a sip of a drink from a glass'. Find frequency of the letter 'i'
[A]: 4


[Q]: Sentence: 'a truck with a camper sits parked in some vegetation'. Find frequency of the letter 's'
[A]: 3


[Q]: Sentence: 'a woman holds a wine glass upside down while wearing rabbit ears and staring at a bottle of wine'. Find frequency of the letter 'a'
[A]:
11