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 man in a black wet suit rides an orange surfboard on the water'. Find frequency of the letter 'o'

Answer: 3


Question: Sentence: 'a young girl is brushing her teeth in this dated photo'. Find frequency of the letter 't'

Answer: 5


Question: Sentence: 'a boat and lighthouse are in a wavy, stylized painting'. Find frequency of the letter 'a'

Answer:
7