Answer:
Option C.
Step-by-step explanation:
For a given set of N elements:
{x₁, x₂, ..., xₙ}
The mean is given by:

And the variance is given by:

Then for our set:
{70, 80 ,75, 75, 80}
We have 5 elements, then N = 5
The first thing we need to find is the mean.

Then the variance will be:

The correct option is C, 14.
A 3x+3c
B 9x^2+12x
C -4ab+24a
D 3x-6
E 3x+3
F (x+1)(2x+3)
G x^2+x-6
H 6x^2-31x+18
I 6x-8y+11
J 2x^3+11x^2+17x+6
M=12
40
44
20
250/11
Last one is 33
Answer:
Speed = 80 m/s
Step-by-step explanation:
The formula to find the speed of a wave is found by
Speed = Wavelength x Frequency where the frequency is in HZ and the wavelength is in meters
Speed = 200 * .40
Speed = 80 m/s