Answer:
Ok what is the problem
Step-by-step explanation:
The given plane,
, has normal vector
. Any plane parallel to this one has the same normal vector.
Let
be any point in the plane we want. The plane contains the point (1, 1, -1), so an arbitrary vector in this plane is

and this is perpendicular to
.
So the equation of the plane is

or equivalently,

Answer:

Step-by-step explanation:
Given expression is
.
Now we need to multiply this using FOIL.
F = First 
O = Outside 
I = Inside 
L = Last 
Hence we get :

Answer:

Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 20 - 1 = 19
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 19 degrees of freedom(y-axis) and a confidence level of
. So we have T = 2.861.
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The format of the confidence interval is:

In which
is the sample mean
So
