Which statement describes iron? A. Iron is an insulator because the outer electrons of its atoms can
move easily from one atom to another.
B. Iron is a conductor because each atom shares all of its electrons
with the surrounding atoms.
C. Iron is an insulator because its atoms have the maximum number
of valence electrons.
D. Iron is a conductor because the outer electrons of its atoms can
move easily from one atom to another.

Lab reagent, hypothesis test.a reference solution used as a lab reagent is purported to have a concentration of 5 mg/dl. six samples are taken from this solution and the following concentrations are recorded: (5.32, 4.88, 5.10, 4.73, 5.15, 4.75) mg/dl.these six measurements are assumed to be an srs of all possible measurements from solution.they are also assumed to have a standard deviation of 0.2, a normal distributin, and a mean concentration equal to the true concentration of the solution.carry out a significance test to determine whether these six measurements provide reliable evidence that the true concentration of the solution is actually not 5 mg/dl.