no
No, there would be no reason to.
Yes!
usually it the fathers last name
God has no father he was always there and never born
That would depend on whether the bloods types are both negative or both positive or one of each, If the blood types are both the same then there will be no problem, if the mother has negative blood and the father positive, the baby can be born "blue", which basically means the mothers blood being negative is trying to destroy the fathers positive antibodies from his blood in the baby, this is not too much of a problem as midwives will administer an "anti D" injection to the mother to protect the baby, if untreated the baby will be born with blue lips, toes, fingers and other extremities, a blood transfusion usually sorts any problems and does not have any long term problems for mother or baby.
yes
No, it is not possible.
I believe that you have to wait until the child is born. At that point you may have a blood test done to the baby and if possible from the potential fathers. The test by blood type may help narrow down the field. The best way is to have a DNA test done.
Yes
No.
yes
Not while you are pregnant, that I know of, but after the baby is born you can have the baby, the mom and the possible fathers tested. It's usually a very simple test and takes a week or two to get the results back.