Its hard to tell from that picture, do you have any of her standing level, and preferably a head study. Is there anything in particular makes you think she is a cross?
White is perfectly acceptable CT the ones with white are called parti colour. I'm on phone now op so pic not very clear but she looks whippet to me. I'm guessing she's quite young and pups are more chunky than adults if that is your concern.
only because people keep asking whats she is crossed with my other one is only 12 weeks old but male so probably why they are so different. will try to get pics of them later as the only pics i have of them at the mo are them playing fighting