18.D
19.A
20.C
21.B
theses are going to be your answers
Which components are part of all scientific investigations?
Check all that apply.
scientific question
hypothesis variables
control procedure
conclusion
Answer:
Conclusion
control procedure
scientific question
Explanation:
A Scientific method/investigation is simply the steps that are taken in order to find or get new material or new information that will upgrade already existing information or make it better understood.
The components of a scientific investigation/method are conclusion, control procedure, and scientific question because they are involved in the scientific process of obtaining new information.
B. False their are tons of ethnic islands some I don't even know about even though their are some in city locations their not all there.
Finding the new mean is simple: If ![E[X]=10](https://tex.z-dn.net/?f=E%5BX%5D%3D10)
, then ![E[2X]=2E[X]=20](https://tex.z-dn.net/?f=E%5B2X%5D%3D2E%5BX%5D%3D20)
.
Meanwhile, the standard deviation is the square root of the variance, which is given by
![V[X]=E[X^2]-E[X]^2\implies V[2X]=E[(2X)^2]-E[2X]^2=4E[X^2]-(2E[X])^2](https://tex.z-dn.net/?f=V%5BX%5D%3DE%5BX%5E2%5D-E%5BX%5D%5E2%5Cimplies%20V%5B2X%5D%3DE%5B%282X%29%5E2%5D-E%5B2X%5D%5E2%3D4E%5BX%5E2%5D-%282E%5BX%5D%29%5E2)
![\implies V[2X]=4\underbrace{\left(E[X^2]-E[X]^2\right)}_{V[X]}=12](https://tex.z-dn.net/?f=%5Cimplies%20V%5B2X%5D%3D4%5Cunderbrace%7B%5Cleft%28E%5BX%5E2%5D-E%5BX%5D%5E2%5Cright%29%7D_%7BV%5BX%5D%7D%3D12)
and so the new standard deviation would be ![\sqrt{V[2X]}=\sqrt{12}=2\sqrt3](https://tex.z-dn.net/?f=%5Csqrt%7BV%5B2X%5D%7D%3D%5Csqrt%7B12%7D%3D2%5Csqrt3)
.
