Answer:
1. 1, 2, 4 all show some form of refraction as the bending of a light ray when passing from one media to another.
Explanation:
Number 4 is the most accurate as it also shows some light being reflected and the bending of the refracted light ray in the correct direction for going from a medium of low refractive index (air) into a higher refractive index material (crown glass)
I can not solve the problem if I do not have the mass.
Answer:
Explanation:
Given
Length of rope 
Weight of rope 
weight density
Work done to lift rope 33 m


![W=73.45\left [ \left ( \frac{h^2}{2}\right )\right ]^{33}_0](https://tex.z-dn.net/?f=W%3D73.45%5Cleft%20%5B%20%5Cleft%20%28%20%5Cfrac%7Bh%5E2%7D%7B2%7D%5Cright%20%29%5Cright%20%5D%5E%7B33%7D_0)