Answer:

Step-by-step explanation:
The confidence interval for the population mean x can be calculated as:

Where x' is the sample mean, s is the population standard deviation, n is the sample size and
is the z-score that let a proportion of
on the right tail.
is calculated as: 100%-99%=1%
So, 
Finally, replacing the values of x' by 308, s by 17, n by 15 and
by 2.576, we get that the confidence interval is:

Answer:
74
Step-by-step explanation:
(8x10) - 6 =
80 - 6 = 74
I did the work for you but the answer would be 1 second
Answer:
Four unique planes
Step-by-step explanation:
Given that the points are non co-planar, triangular planes can be formed by the joining of three points
The points will therefore appear to be at the corners of a triangular pyramid or tetrahedron such that together the four points will form a three dimensional figure bounded by triangular planes
The number of triangular planes that can therefore be formed is given by the combination of four objects taking three at a time as follows;
₄C₃ = 4!/(3!×(4-3)! = 4
Which gives four possible unique planes.