Answer:
Kindly check explanation
Step-by-step explanation:
The alpha level set at the beginning of of an experiment is used by the researcher to the limit the probability if making a type 1 error. The type 1 error is committed when a true null hypothesis is incorrectly rejected.
The type 2 error on the other hand is committed when fail to reject a false null hypothesis.
Hence, in other to forestall the risk of incorrectly rejecting a true null hypothesis, the alpha level is set.
When critical region is split across both tails of the distribution, The z-score boundaries at an alpha level α = .05
α = .05 (95% confidence level)
When region is split into 2:
α/2 = .05/2
α/2 = 0.025
Loooking up the z table for the Zscore with probability of 0.025
Zscore = ±1.96
Answer:
The alternative hypothesis being tested in this example is that the tire life is of more than 60,000 miles, that is:

Step-by-step explanation:
A tire manufacturer has a 60,000 mile warranty for tread life. The company wants to make sure the average tire lasts longer than 60,000 miles.
At the null hypothesis, we test if the tire life is of at most 60,000 miles, that is:

At the alternative hypothesis, we test if the tire life is of more than 60,000 miles, that is:

I'm sorry I do not know how to set up the equation but I do know it's 17 hours because 7(30)= 210 and 10(20)= 200 and 200+210=410
Answer:
The number of ways is equal to 
Step-by-step explanation:
The multiplication principle states that If a first experiment can happen in n1 ways, then a second experiment can happen in n2 ways ... and finally a i-experiment can happen in ni ways therefore the total ways in which the whole experiment can occur are
n1 x n2 x ... x ni
Also, given n-elements in which we want to put them in a row, the total ways to do this are n! that is n-factorial.
For example : We want to put 4 different objects in a row.
The total ways to do this are
ways.
Using the multiplication principle and the n-factorial number :
The number of ways to put all 40 in a row for a picture, with all 12 sophomores on the left,all 8 juniors in the middle, and all 20 seniors on the right are : The total ways to put all 12 sophomores in a row multiply by the ways to put the 8 juniors in a row and finally multiply by the total ways to put all 20 senior in a row ⇒ 