Well, an endoskeleton is an internal skeleton, like humans have.
Pro: Bones do not get broke as easily, since they are inside of the body. Bones that break also heal more quickly in an endoskeleton, since they have tissue and blood surrounding it and transferring nutrients.
Con: The flesh can get easily damaged. There is no shedding with endoskeletons, so a new skeleton cannot be grown in the event of an injury.
Im pretty sure its
A. Number of Organisms
B. Amount of Matter
A million sorrys if im wrong :(
Forward spatter is the blood that is ejected out of the exit wound,going the same direction as the bullet.back spatter is the blood ejected out of the entry wound,travelling against the line of fire and towards the shooter.