A 'displacement' always consists of a magnitude and a direction. The two cars you just described have displacements with the same magnitude ... 5 km. But if they didn't both drive in the same direction, then their displacements are different.
Remember:
-- 10 m/s² up and 10 m/s² down are different accelerations
-- 30 mph East and 30 mph West are the same speed but different velocity.
-- 5 km North and 5 km South are the same distance but different displacement.
B, Studying how ones' character changes over time... That's the only one that has to deal with personality.
Answer:
1) True, 2) True, 3) False, 4) False, 5) False
Explanation:
1) True. Dissipative energy cannot be recovered, in general it is a form of heat
2) True. The dissipation can be by radiation, heat
3) False. Mechanical energy is divided into K and U but not in equal parts
4) False. When there are dissipative interactions, part of the mechanical energy is set in the form of heat, so its value decreases
5) False. Mechanical energy is the sum of those two energies