The number of arrivals per minute at a bank located in the central business district of a large city was recorded over a period of 200 minutes with the results shown in the table below.
Complete parts (a) and (b)
Arrivals          Frequency
0                         16
1                          37
2                          48
3                          41
4                          27
5                          17
6                            8
7                            3
8                             1

Required

a. Compute the expected number of arrivals per minute.
μ=___( please type as an integer or a decimal)

b. Compute the standard deviation
σ=___(please round to three decimal places as needed)