I wonder if you mean to write ![\sqrt[3]{256}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B256%7D)
in place of 
...
If you meant what you wrote, then we have
If you meant to write (the cube root of 256), then we could go on to have
![\sqrt[3]{256}=\sqrt[3]{16^2}=\sqrt[3]{(4^2)^2}=\sqrt[3]{4^4}=\sqrt[3]{4^3\cdot4}=4\sqrt[3]4](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B256%7D%3D%5Csqrt%5B3%5D%7B16%5E2%7D%3D%5Csqrt%5B3%5D%7B%284%5E2%29%5E2%7D%3D%5Csqrt%5B3%5D%7B4%5E4%7D%3D%5Csqrt%5B3%5D%7B4%5E3%5Ccdot4%7D%3D4%5Csqrt%5B3%5D4)
Answer: in 95% of races, his finishing time will be between 62 and 64 seconds.
Step-by-step explanation:
The empirical rule states that for a normal distribution, nearly all of the data will fall within three standard deviations of the mean . The empirical rule is further illustrated below
68% of data falls within the first standard deviation from the mean.
95% fall within two standard deviations.
99.7% fall within three standard deviations.
From the information given, the mean is 63 seconds and the standard deviation is 5 seconds.
2 standard deviations = 2 × 0.5 = 1
63 - 1 = 62 seconds
63 + 1 = 64 seconds
Therefore, in 95% of races, his finishing time will be between 62 and 64 seconds.
The answer to your question is option b
There are mistakes in the answer options attached. These are the correct ones.
a. The group that received the bottle of solution is the control group.
b. The group that received the bottle of solution that did not contain the ingredients that are meant to lessen wrinkles is the control group.
c. Both the groups are control groups.
d. Neither group is an control group.
Answer:
B. The group that received the bottle of solution that did not contain the ingredients that are meant to lessen wrinkles is the control group
Step-by-step explanation:
In an experiment of this type, the control group is the group that does not contain the treatment. So in this group The effect of the treatment unknown unlike the experimental group which gets the treatment that the researcher is trying to find it's effect.
I. Conclusion, the group that got bottles that did not contain Ingredients for wrinkles lessening is the control group.
