(a) An optically inactive compound A (C6H10O4) can be resolved into enantiomers and has the following NMR spectra: 13C NMR: ? 13.5, ? 41.2, ? 177.9 1H NMR: ? 1.13 (6H, d, J = 7 Hz); ? 2.65 (2H, quintet, J = 7 Hz); ? 9.9 (2H, broad s, disappears after D2O shake) Draw either enantiomer, including wedge/dash bonds. (b) Give the structure for an isomer of compound A that has a melting point that is appreciably different from that of A yet NMR spectra that are almost identical to those of A. Include wedge/dash bonds.