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

Q: Sentence: 'a man riding a skateboard up the side of a ramp'. Find frequency of the letter 'u'

A: 1
****
Q: Sentence: 'a glass a rope and a pair of scissors'. Find frequency of the letter 's'

A: 6
****
Q: Sentence: 'a grizzly bear standing on concrete in an iron barred cage'. Find frequency of the letter 'n'

A:
7
****