Answer:
Brand 1 Brand 2 Difference
37734 35202 2532
45299 41635 3664
36240 35500 740
32100 31950 150
37210 38015 −805
48360 47800 560
38200 37810 390
33500 33215 285
Sum of difference = 2532+ 3664+740+150 −805+ 560 +390 +285 = 7516
Mean = 
Mean = 
a) d= 939.5


=1441.21
b)SD= 1441.21
c)Calculate a 99% two-sided confidence interval on the difference in mean life.
confidence level =99%
significance level =α= 0.01
Degree of freedom = n-1 = 8-1 =7
So, 
Formula for confidence interval 
Substitute the values
confidence interval 
confidence interval
to 
Confidence interval
to 
Answer:
x = 6
Step-by-step explanation:
2/3=8/x+6
Using cross products
2 * (x+6) = 3*8
2(x+6) = 24
Divide by 2
x+6 =12
Subtract 6
x = 6
Answer:
I dont really do this kind of work but i think its A
Step-by-step explanation:
Not sure. has the same question
Answer: B
Step-by-step explanation:
A quadratic equation has degree 2.