Answer:
Step-by-step explanation:
Given that n =30, x bar = 375 and sigma = 81
Normal distribution is assumed and population std dev is known
Hence z critical values can be used.
For 95% Z critical=1.96
Margin of error = 
Confidence interval = 375±29
=(346,404)
B) 99% confidence
Margin of error = 2.59*Std error =38
Confidence interval = 375±38
=(337, 413)
C) For 90%
Margin of error = 20
Std error = 20/1.645 = 12.158
Sample size

Atleast 44 people should be sample size.
Answer:
4
Step-by-step explanation:
i hope u understand !0k ?????

whatever the amounts of "x" and "y" are, they must add up to 5Liters
thus x + y = 5
and whatever the concentrated quantity is in each, they must add up to (5)(0.14)
notice, that we use the decimal notation for the amount of juice concentration, that is, 15% is just 15/100 or 0.15, and 14% is just 14/100 or 0.14 and so on, recall that "whatever% of something" is just (whatever/100)*something
thus

solve for "x", to see how much of the 15% juice will be needed
what about "y"? well, y = 5 - x
Answer:
The Y intercept adds on +6 every time.
Step-by-step explanation:
Hope this helps! :3