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 dog sitting in the back of a truck flat bed'. Find frequency of the letter 'h'

Answer: 1


Question: Sentence: 'a group of people are playing soccer on a beach'. Find frequency of the letter 'l'

Answer: 2


Question: Sentence: 'a round cheese pizza with toppings on a white plate'. Find frequency of the letter 'o'

Answer:
3