Assessing Sample Size for the Number of "Walk-Ins"

Part of my job description is to teach Recruiters their daily individual tasks and how to properly manage their time. One of the Recruiter duties is to generate appointments in many different ways. They can visit high schools, Shopping Centers, or any other public places available within their Recruiting zone; their main goal is to find as many qualified potential recruits / applicants. They can also make house calls and call people at their homes. Perhaps the easiest way to make appointments is from people who walk into a Recruiting Station seeking information on their own.

I asked one of the Station Commanders who is also one the most knowledgeable and experienced Leaders in our Battalion to keep track and observe how many "Walk-ins" his Station had each day morning and afternoon for two consecutive weeks; and how many enlistments would come from people that “walked-in” to his station as opposed to how many his recruiters generated.

We collected data to reflect the number of "walk-ins" over a ten work day (Monday thru Friday) period. Additionally, I asked him collect data for 5 additional days (days 10th thru 15th).

Furthermore I plan to compare the morning to the afternoon to determine which is more productive for "walk-ins". I will display the results in a table with the mornings labeled (9:00 AM until 11:59 AM) "AM" and the afternoon labeled (12:00 noon until 5:00 PM) "PM".

PART 1:
1. Using Excel, prepare a frequency distribution from the data collected.
2. Calculate the standard deviation of the data collected.
3. Is this a normal distribution?
4. What are the implications?

# OF "WALK-IN'S"
DAY DAY OF WEEK AM(9-11:59 AM) PM(12-5 PM)
1 MONDAY 2 3
2 TUESDAY 3 1
3 WEDNESDAY 2 2
4 THURSDAY 0 2
5 FRIDAY 2 0
6 MONDAY 5 2
7 TUESDAY 2 5
8 WEDNESDAY 4 3
9 THURSDAY 3 3
10 FRIDAY 4 2
TOTALS 27 23

PART 2:
1. Is the larger sample changing anything?
2. Is the mean increasing or decreasing?
3. Do you think the current sample I have is enough to paint an accurate picture, or do I need a much larger sample?

# OF "WALK-IN'S"
DAY DAY OF WEEK AM(9-11:59 AM) PM(12-5 PM)
1 MONDAY 2 3
2 TUESDAY 3 1
3 WEDNESDAY 2 2
4 THURSDAY 0 2
5 FRIDAY 2 0
6 MONDAY 5 2
7 TUESDAY 2 5
8 WEDNESDAY 4 3
9 THURSDAY 3 3
10 FRIDAY 4 2
11 MONDAY 3 4
12 TUESDAY 3 3
13 WEDNESDAY 5 3
14 THURSDAY 4 2
15 FRIDAY 2 1
TOTALS 44 36

Thanks in advance for your assistance.