The region where warm and cold air masses meet is called a front
<span>Polymers are small molecular units joined together in large molecules.
hope this helps!</span>
The total displacement of the toy car at the given positions is 0.
The given parameters;
- <em>First displacement of the car, = 5 cm left</em>
- <em>Second displacement of the car, = 8 cm right</em>
- <em>Third displacement of the car, = 3 cm to the left</em>
The total displacement of the car is calculated as follows;
- <em>Let the </em><em>left </em><em>direction be "</em><em>negative </em><em>direction"</em>
- <em>Let the </em><em>right </em><em>direction be "</em><em>positive </em><em>direction"</em>

Thus, the total displacement of the toy car at the given positions is 0.
Learn more about displacement here: brainly.com/question/18158577
Kinetic friction (also referred to as dynamic friction) is the force that resists the relative movement of the surfaces once they're in motion.
https://www.khanacademy.org › stat...
Static and kinetic friction example (video) | Khan Academy
Answer a would be static friction
Answer b is fluid friction
(Air resistance is fluid friction. Fluid friction is the friction experienced by objects which are moving in a fluid and the air is a fluid.)
Answer c is static friction
ANSWER D IS KINETIC FRICTION
Hope this helps :D