Deduce the structure of an unknown compound from the following spectroscopic and analytical characteristics. Molecular formula: C8H16O 1HNMR:=0.90(t,3H),1.01.6(m,8H),2.05(s,3H),2.25(t,2H)ppm 13 C NMR: seven signals between 14.0 and 43.8ppm, and one at 208.9ppm IR: 1715cm1 UV: max()280(15)nm MS: m/z128(M+); intensity of (M+1)+peak is 9% of (M+)peak; important fragments are at m/z=113(M15)+,m/z=85 (M43)+,m/z=71(M57)+,m/z=58(M70)+(the second largest peak), and m/z=43(M85)+(the base peak). Draw the unknown compound