statistics... I am clueless and appreciate any help

#1
There are two hundred faculty members at Auburn University and faculty salaries are known to be normally distributed with a mean of $82,000 and a standard deviation of $5,000.

· If a faculty member is chosen at random, what is the probability that their salary is between $75,000 and $79,000?
· There are twenty-two faculty members in the college of business. What is the probability that the average salary in the college of Business is more than $85,000?
· There are three faculty members in the Anthropology Department. What is the probability that the average salary in the Anthropology Department is less than $78,000?
 
#3
Also clueless and any help appreciated

Hi, I'm an utter idiot for stats.
I'm trying to do something which should be very simple.
I'm trying to compare the mean hours of sunlight in the months of April & May in Scotland with the mean hours of sunlight for the months of June - August.
I'm not sure what test allows me to compare them appropriately.

e.g.

Mean Sunlight hours for April = 178.5hrs
Mean sunlight hours for May = 157.1hrs
Mean sunlight hours for June = 99.2
Mean sunlight hours for July = 137.3
Mean sunlight hours for August = 117.7

Therefore mean for Apr/May = 167.8
and Mean for June-Aug = 118.07

What is the correct test to show that April and May were sunnier than the rest of the summer?
 
#4
Ok, it is obvious that April through May were sunnier than June through August, as the mean is higher. What next depends on depth of analysis. Generally to compare two means you use a t-test, though I'm not sure of equality of group sizes, you might think about a Mann-Whitney.

I'm wondering though, as I said, what level of analysis you want, because it seems very basic.