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: 'many white birds flying above a river that flows in front of a forest'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a burning wood stove has a tea pot sitting on top of it and is full of wood'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'statue of a rider on horseback holding a pole with a cross on it'. Find frequency of the letter 'a'

Answer:
5