How does the concentration of organisms in a body of water affect the rate of oxygen consumption?

How do you create a data set with 8 points in it that has a mean of approximately 10 and a standard deviation of approximately 1?

X– 4 = 12.5 can be written in words as

The roof of a farm silo is the shape of a hemisphere and is made of sheet tin. if the diameter of the silo is 126.5 feet, how much sheet tin is needed to make the roof? (use π = 3.1416.)