Help with how to phrase questions about A Pet’s death

Hi, yesterday a veterinarian told me my 11 year old Labrador has an inoperable lung tumor that will " take her," and he called it a " ticking time bomb". She is not suffering, and he said when it happens, it could take 15 minutes. I would really like to ask my cards how she's going to feel, and if she'll go peacefully, but I'm very inexperienced, and I was hoping someone could help me figure out what kind of spread to do?