After conducting a five-day travel fair at the Mid-valley Exhibition Hall, Harmony Tour and Travel is reviewing the number of complaints received per day. Following are the number of complaints with their respective probabilities received by the company in a day:

Number of Complaints Probability 1 0.35 2 0.20 3 0.25 4 0.15 5 0.05

a. Calculate the expected number of complaints received by Harmony Tour and Travel in a day.

b. Compute the variance and standard deviation for the number of complaints received per day.