Answer:
A sample of 179 is needed.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
That is z with a pvalue of 
, so Z = 1.44.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
A previous study found that for an average family the variance is 1.69 gallon?
This means that 
If they are using a 85% level of confidence, how large of a sample is required to estimate the mean usage of water?
A sample of n is needed, and n is found for M = 0.14. So
Rounding up
A sample of 179 is needed.
It’s 4.08x10 to the 6 power. Which is answer A
Answer:
The question is incomplete, so I will describe the sine regression model.
The function
y = 0.884 sin(0.245x - 1.093) + 0.400
correspond to the general equation:
y = a sin(bx - c) + d
where:
a = 0.884
b = 0.245
c = 1.093
d = 0.400
The amplitude of the function is computed as follows:
amplitude = |a| = 0.884
The period of the function is computed as follows:
period = 2π/|b| = 25.6456
The phase shift of the function is computed as follows:
phase shift = c/b = 4.4612 to the right (because there is a minus sign before c in the equation)
The vertical shift of the function is computed as follows:
vertical shift = d = 0.400
I believe the answer is Monday!
Poin slope form is
y-y1=m(x-1)
the answer is A
