Access the Chart of the Nuclides for 2,200 m/sec or thermal neutrons, and determine the total microscopic cross sections for the following isotopes: 1. U235 2. Pu239 3. Be9 4. C12 Estimate their: 1. Number densities, 2. Total macroscopic cross-sections, 3. Total mean free paths. Calculate the total cross sections and the mean free paths of thermal neutrons in the following moderators: 1. H2O 2. D2O A stainless steel composition is 69 w/o Fe, 17 w/o chromium, 12 w/o nickel and 2 w/o molybdenum. Calculate its absorption macroscopic cross section and its absorption mean free path for thermal neutrons. For a thermal neutron flux of 1010 neutrons / (cm2.sec), estimate the absorption rate density in the stainless steel.