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 herd of zebra standing on top  of a grass covered field'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'a woman holds the reins of a saddled horse'. Find frequency of the letter 'm'

Answer: 1


Question: Sentence: 'a man outside in the snowing getting ready to ski'. Find frequency of the letter 't'

Answer:
5