Answer :
If the mean = 54, 1 standard deviation (+1σ) above the mean = 54+6 = 60
1 standard deviation (-1σ) below the mean = 54 - 6 = 48
68% of the data of a normal distribution lies between -1σ and +1σ: between 48 - 60 requests
between 54 - 60 requests (between the mean and +1σ) is half of this percentage: 68/2 = 34%
Answer: 34%