The elasticity of a polymer is affected by the concentration of a reactant. from the chemistry of the process we know that when a low concentration is used, the true mean elasticity is 55, and when a high concentration is used the true mean elasticity is 60. random variation is known to be due to chemical impurities and the standard deviation of elasticity is 4, regardless of concentration. if random samples of size 16 are taken at both low and high concentrations, find the probability that x¯ high − x¯ low ≥ 2.