/sci/ - Science & Math

I'm sorry if these seem like stupid questions, but I'm interested in knowing the answer to them:
1. Do dogs know they are going to die, or do they just operate on instinct? How much do dogs know about their mortality?
2. If we have a number line and we plot the point +6, is that closer to +infinite then to -infinite or is it the same distance?
3. I understand that 0.999.... = 1. But the integer part of a number is basically the decimal chopped off - when you graph y=int(x), you get a stair-case looking graph. What is the integer part of 1.99.... - 1 or 2?