In this task, you need to count the number of times the given letter appears in the given sentence.
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Question: Sentence: 'a black computer with a screen reading "press any key to begin."'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'flower in a vase full of water sitting on a stand '. Find frequency of the letter 'l'

Answer: 3


Question: Sentence: 'a man smiles as he hands his frisbee to another person'. Find frequency of the letter 'o'

Answer:
3