A sample of acetone (propan-2-one, (CH 3 )2CO) is enriched in 13 C so that exactly 40% of the C atoms are 13 C and the other 60% are 12 C (spin I = 0). The 13 C atoms are randomly distributed. How many isotopomers are there, and what are their relative proportions? (Ignore the isotopes of hydrogen and oxygen.) Sketch the 1H-decoupled 13 C spectrum of each isotopomer, assuming that one-bond 13 C 13 C couplings are 50 Hz. Sketch the 1H-decoupled 13C spectrum of the whole sample.