The isotope 18F is a radionuclide used in medical diagnoses of tumors and, although usually produced by the 18O(p,n)18F reaction, it can also be produced by irradiating lithium carbonate (Li2CO3) with neutrons. The neutrons interact with with 6Li to produce tritons (nuclei of 3H), which, in turn, interact with the oxygen to produce 18F. What are the two nuclear reactions?