The oxidation number of lead (pb) in the compound pbcl2 has to be

answer this and explain how i would go about getting the answer/how to solve for the answer

Asynthetic fiber used in manufacturing carpet has tensile strength that is normally distributed with mean 75.5 psi and standard deviation 3.5 psi. how is the standard deviation of the sample mean changed when the sample size is increased from n equals 8 to n equals 47