What statement best defines work?

a.) work is the time it takes to move an object once acted upon by a force.
b.) work occurs when balanced forces act on an object and cause movement in the direction of these forces
c.) work occurs when a force causes motion of an object, and this motion is in the same direction of the applied force.
d.) work is the distance over time that an object moves once acted upon by a force.

What is the acceleration of a spaceship that is initially at rest and then speeds up to 220 m/s in 20 seconds

The intensity of a polarized electromagnetic wave is 12 w/m^2. part a) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=0∘ with the plane of polarization? part b) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=30∘ with the plane of polarization? part c) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=45∘ with the plane of polarization? part d) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=60∘ with the plane of polarization? part e) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=90∘ with the plane of polarization?

Which of the following are appropriate acceleration units?