Benzaldehyde forms 2 stereoisomeric oximes. How may their configurations be determined?

X-ray crystallography or nmr?

There are 3 xylenes. Their melting points are 13 degrees C, -24 degrees C, and -48 degrees C. Nitration of the isomer with the 13 degrees C mp results in only one mononitrated product. The isomer with mp=-23 degrees C gives 2 mononitrated products, and the isomer with mp -48 degree C gives 3 mononitrated products. Write the structure for each respective mp isomer and their nitrtion products.