A free body diagram of a brick on an inclined plane is shown below. What is the mechanical advantage of the inclined plane?

With i really need the correct answer!

Light from two different sources are incident upon the same side of a polarizing filter. light from one source is polarized with total intensity ip, while light from the other source is unpolarized with total intensity iu. as you rotate the polarizing filter through 360 degrees, the intensity of the transmitted light on the other side varies by a factor of 9. what is the relative intensity of the initial polarized source to the unpolarized source, or ip/iu?

All phase changes are .an example of a phase change is an ice cube melting