21 points: complete the attached questions and show all working out. must use

Astudent wears sunglasses to her read a book more easily which wave interaction occurs as light passes from the air into the plastic lenses? a polarization b.refraction c.diffraction d. interference

Polly is pushing a box across the floor with a force of 30 n. the force of gravity is –8 n, and the normal force is 8 n. which value could describe the force of friction if polly could not move the box?

Abumper car with a mass of 250 kg is traveling at a speed of 4 m/s. this bumper car collides and sticks to a second bumper car with a mass of 250 kg, which is initially at rest. what is the final speed of these two bumper cars after the collision, assuming they remain stuck together?