5) Answer the following questions. a) DBE b) What signal(s) in the 13C NMR spectrum are useful to help determine the structure? Why? c) What signal(s) in the HSQC spectrum are useful to help determine the structure? Why? d) What signal(s) in the HMBC spectrum are useful to help determine the structure? Why? -6.728 27 6.700 869'9- 2.858 - 2.615 2.582 KI 1H NMR, C24H23 NO2 500 MHz, CDCI: a ww TT 6.74 6.70 6.68 6.72 ppm 6.58 6.57 6.56 6.55 ppm 6.00 2.95 6.05 ppm 2.90 2.85 2.80 2.75 2.70 2.65 ppm 2.60 2.55 SETE - 2.208