Answer:
![Var(X) = E(X^2) -[E(X)]^2 = 4.97 -(1.61)^2 =2.3779](https://tex.z-dn.net/?f=%20Var%28X%29%20%3D%20E%28X%5E2%29%20-%5BE%28X%29%5D%5E2%20%3D%204.97%20-%281.61%29%5E2%20%3D2.3779)
And the deviation would be:

Step-by-step explanation:
For this case we have the following distribution given:
X 0 1 2 3 4 5 6
P(X) 0.3 0.25 0.2 0.12 0.07 0.04 0.02
For this case we need to find first the expected value given by:

And replacing we got:

Now we can find the second moment given by:

And replacing we got:

And the variance would be given by:
![Var(X) = E(X^2) -[E(X)]^2 = 4.97 -(1.61)^2 =2.3779](https://tex.z-dn.net/?f=%20Var%28X%29%20%3D%20E%28X%5E2%29%20-%5BE%28X%29%5D%5E2%20%3D%204.97%20-%281.61%29%5E2%20%3D2.3779)
And the deviation would be:

Answer:
C
Step-by-step explanation:
calculate like terms, then it is pretty simple from there.
Answer:
There is no way to tell
Step-by-step explanation:
You could be way taller than your parents, the same height, or shorter. There are too many variables at play here.
3280.839895 ft = 1 km
60 ft = 60/3280.839895 = 0.018288 km
60 ft/s = 0.018288 km/s = 0.018288 x 60 x 60 = 65.8368 km/h
The answer to 20+50 is 72