During a snowball ght, two students. throw snowballs at each other at the same time. Imagine that both snowballs have the same mass and are thrown with the same initial soeecl. The snowballs collide in miclair and stick together, then fall clown. Immediately after the collision. what is the nal momentum of the combinecl mass before falling clown {clon't allow time for gravityr to act]? [Insert the number only without units.)