A forensic team collecting evidence from a crime scene discovers a clump of hair grasped in the victim's hand, very likely removed forcibly from the suspect. What factor would limit the usefulness of this evidence if no 'persons of interest' have been identified? A) The suspect's DNA is not on file. B) No DNA can be extracted from the sample. C) The hair doesn't exhibit clear characteristics of ethnic origin. D) The hair has been dyed so suspect's natural color can't be determined.

Astone is thrown with a speed v0 and returns to earth, as the drawing shows. ignore friction and air resistance, and consider the initial and final locations of the stone. which one of the following correctly describes the change δpe in the gravitational potential energy and the change δke in the kinetic energy of the stone as it moves from its initial to its final location? options a.δpe = 0 j and δke = 0 j b.δpe is positive and δke is negative c.δpe = 0 j and δke is positive d.δpe is negative and δke is positive e.δpe = 0 j and δke is negative