Solve the below problem:
Q: Suppose that X1 , X2 , and X3 represent the thickness in micrometers of asubstrate, an active layer, and a coating layer of a chemical product, respectively. Assume thatX1 , X2 , and X3 are independent and normally distributed with µ1 = 10000, µ2 = 1000, µ3 = 80, s1 = 250, s2 = 20,and s3 = 4, respectively. The specifications for the thickness of the substrate, active layer, and coating layer are 9200 < x1 <10,800,950 < x2 <1050, and 75< x3 <85, respectively. What proportion of chemical products meets all thickness specifications? Which one of the three thicknesses has the least probability of meeting specifications?