The mean number of close friends for the population of people living in the u. s. is 5.7. the standard deviation of scores in this population is 1.3. an investigator predicts that the mean number of close friends for introverts will be significantly different from the mean of the population. the mean number of close friends for a sample of 26 introverts is 6.5. do these data support the investigator's prediction? use an alpha level of .05.

The investigators prediction was right that the mean number of close friends of introvert are different from the mean of the population

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 5.7

Sample mean, = 6.5

Sample size, n = 26

Alpha, α = 0.05

Population standard deviation, σ = 1.3

First, we design the null and the alternate hypothesis

We use Two-tailed z test to perform this hypothesis.

Formula:

Putting all the values, we have

Now,

Since,  

We reject the null hypothesis and accept the alternate hypothesis. Thus, the investigators prediction was right that the mean number of close friends of introvert are different from the mean of the population.

6,250

step-by-step explanation:

to get the area, multiply 360 by 160.(57,600)

to find out how many bags of fertilizer it will take, first figure out how many square feet one bag can hold. divide 1000 by 8(125) to get the unit rate(how many square feet one pound of fertilizer can hold)and multiply it by 50(6250). if i haven't made a mistake, that is the answer.

answer:

a=9

step-by-step explanation: lmk if you need a explanation