In this task, you need to count the number of times the given letter appears in the given sentence.

[Q]: Sentence: 'a bus with two floors belonging to london country'. Find frequency of the letter 't'
[A]: 4


[Q]: Sentence: 'an image of a street sign with a corner restaurant'. Find frequency of the letter 'u'
[A]: 1


[Q]: Sentence: 'a child wearing skis  standing on a snow bank'. Find frequency of the letter 'r'
[A]:
1