Time spent using e-mail per session is normally distributed, with mu equals μ=13 minutes and sigma equals σ=2 minutes. complete parts (a) through (d). a. if you select a random sample of 50sessions, what is the probability that the sample mean is between 12.8 and 13.2 minutes? b. if you select a random sample of 50sessions, what is the probability that the sample mean is between 12.5 and 13 minutes? c. if you select a random sample of 100sessions, what is the probability that the sample mean is between 12.8 and 13.2 minutes? d. explain the difference in the results of (a) and (c). choose the correct answer below. the sample size in (c) is greater than the sample size in (a), so the standard error of the mean (or the standard deviation of the samplingdistribution) in (c) is ▼ less greater than in (a). as the standard deviation ▼ increases decreases , values become ▼ less more concentrated around the mean. therefore, the probability of a region that includes the mean will always ▼ decrease increase when the sample size increases.

2/3

step-by-step explanation:

the slope of a line is equal to the rise/run. in this case the line rises 2 units for every +3 units it moves

step-by-step explanation: so we look at the formula un = a + (n-1)d

un is the amount of seats

n is the nth term aka row number

a is the original sequence/row number

d is the difference between each term

so in this a=22 d=6 and n can remain as n because we are simply formjng a rule

lets put these in the equation

un=22+(n-1)(6)

this is your answer to part a

however

lets double check that this is correct, we'll try putting it into the second term

un=a+(n-1)d

u2=22+(2-1)(6)

u2=22+6

u2=28

as the question said the second row has 28 seats so now we know the formula we made is correct.

as for part b

un=a+(n-1)

its asking us to find a row with 100 seats.

remember un was the amount of seata so all we do is substitute this in.

un=100 a=22 d=6

un=a+(n-1)d

100=22+(n-1)(6)

so now we simplify to find n which is the row number.

100-22=22+(n-1)(6)-22

78=(n-1)(6)

78/6=(n-1)(6)/6

13=n-1

13+1=n-1+1

14=n

so now we know that in the 14th row there is 100 seats.

hope this and that you understood! its my first time using the app or anyone out on here : p its also me to revise so a bunch! ask more questions if you dont understand ☺