Organic chemistry homework help

1) Would it better to use 1H NMR or 13C NMR spectroscopy to distinguish compounds H-J?
Explain your answer (HINT: think about # of signals produced)
2) The coupling constant for protons in the compound shown below are Jab=10 and Jac=6
Identify protons A,B, and C
3) Propose a structure that is consistent with following molecular formula and 1H NMR
data:
Molecular Formula C5H10O
Clearly label (a,b, … so on) all protons and assign the chemical shifts, in your
proposed structure