Undercooked pasta... assuming you mean the dried sort... is already fully cooked; it just needs to be heated and rehydrated. It's perfectly safe to eat right out of the box.
Dogs in general have digestive systems that are pretty good at dealing with undercooked or raw food, because they're not very good cooks.
if a dog eats ants its perfectly fine dogs eat everything
the dog eats poo
Poop
Not much unless he eats too much.
The duck will get sick
He won't digest it and it may make it sick.
you should call a vet
it is an overdose, it can give your dog an infection internaly, dont do it
you have to rush it to the closest hospital or vet
Nothing. They are harmless.
if he/she doesnt have any health problems, nothing should happen.
I would call poison control and your local vet.