Answer:


And we are 95% confident that the true difference means are between 
Step-by-step explanation:
We know the following info:
sample mean for group 1
sample mean for group 2
sample standard deviation for group 1
sample standard deviation for group 2
sample size group 1
sample size group 2
We want to find a confidence interval for the difference of means and the correct formula to do this is:

Now we just need to find the critical value. The confidence level is 0.95 then the significance is
and
. The degrees of freedom are given by:

The critical value for this case would be :
And replacing into the confidence interval formula we got:


And we are 95% confident that the true difference means are between 
Correct answer is 6... NOT 7...
Hypotenuse = 22*sq root (2)
I'm guessing you need to know the length of the triangle legs?
The triangle leg of a 45 45 90 triangle = hypotenuse / sq root (2)
triangle leg= 22* sq root (2) / sq root (2)
triangle leg=22
Answer and Step-by-step explanation: Spherical coordinate describes a location of a point in space: one distance (ρ) and two angles (Ф,θ).To transform cartesian coordinates into spherical coordinates:


For angle θ:
- If x > 0 and y > 0:
;
- If x < 0:
; - If x > 0 and y < 0:
;
Calculating:
a) (4,2,-4)
= 6
For θ, choose 1st option:
b) (0,8,15)
= 17


The angle θ gives a tangent that doesn't exist. Analysing table of sine, cosine and tangent: θ = 
c) (√2,1,1)
= 2

= 

d) (−2√3,−2,3)
= 5

Since x < 0, use 2nd option:



Cilindrical coordinate describes a 3 dimension space: 2 distances (r and z) and 1 angle (θ). To express cartesian coordinates into cilindrical:

Angle θ is the same as spherical coordinate;
z = z
Calculating:
a) (4,2,-4)
= 

z = -4
b) (0, 8, 15)
= 8

z = 15
c) (√2,1,1)
= 

z = 1
d) (−2√3,−2,3)
= 4

z = 3
Answer:
h=7
Step-by-step explanation:
Distribute the 4 on the right side
36=4(h+2)
36=4h+8
Subtract 8 on both sides
28=4h
Divide by 4 on both sides
h=7
Hope this helps! :)