Answer:
If im not wrong, the correct answer is 752.4cm cube
Step-by-step explanation:
First, we find volume of hemisphere, then find the volume of the cone, once we get those, we add them together and find our final answer. I hope this helps :)
Step-by-step explanation:
x^3 is a perfect cube, 8 is a perfect cube, so we use difference of cubes.

Cube root of x^3 is x.
Cube root of 8 is 2
So
a=x
b= 2.

Set these equations equal to zero



If we do the discriminant, we get a negative answer so we would have two imaginary solutions,
Thus the only real root is 2.
If you want imaginary solutions, apply the quadratic formula.

and

Answer:
Sampling Error
Step-by-step explanation:
When the researcher randomly selected 200 people, he is creating an sample or subset from the population, that would be all the people in the earth. The error obtained was product of the fact that the analysis he made was estimated from the sample and not the whole population. There is no other mentioned factor that could cause an error, so the answer would be a sampling Error.